UC-NR 


GIFT   OF 
MICHAEL  REESE 


LABORATORY  GUIDE 

OF 

INDUSTRIAL  CHEMISTRY 


BY 

ALLEN   ROGERS 

[IN  CHARGE  OF  INDUSTRIAL  CHEMISTRY,  PRATT  INSTITUTE, 

*  BROOKLYN,  N.  Y. 


SECOND  EDITION 

ENTIRELY  REWRITTEN  AND  ENLARGED 


33   ILLUSTRATIONS 


NEW  YORK 
D.  VAN  NOSTRAND  COMPANY 

25  PARK  PLACE 
1917 


Copyright,  1908,  1917,  by 
D.  VAN  NOSTRAND  COMPANY 


PRESS  OF 

BRAUNWORTH  It  CO. 

BOOK  MANUFACTURERS 

BROOKLYN,   N.   Y. 


PREFACE  TO  SECOND  EDITION 


IN  presenting  this  thoroughly  revised  edition,  the  author 
has  endeavored  to  make  the  laboratory  experiments  touch 
more  closely  upon  present-day  problems  than  was  possible 
in  the  first  edition.  It  has  been  the  aim  to  treat  the  subject 
in  such  a  manner  that  the  processes  described  for  applica- 
tion on  a  small  scale  can  also  be  adopted  to  the  larger 
commercial  basis.  Thus,  in  many  instances,  it  will  be 
noticed  that  the  methods  are  those  in  common  use  at  the 
present  time,  and,  whenever  possible,  actual  factory  prac- 
tice has  been  followed.  The  object,  therefore,  is  to  acquaint 
the  student  of  chemistry  with  actual  commercial  problems 
by  bringing  to  his  experience  practical  methods  of  hand- 
ling materials  on  a  large  scale;  the  care  and  use  of 
machinery;  the  cost  of  raw  materials;  transportation; 
wage  system;  the  handling  of  men;  and  shop  discipline. 

This  idea  is  being  carried  out  at  Pratt  Institute  through 
a  foremanship  system  of  instruction,  in  which  groups  of 
students  are  assigned  to  work  in  model  plants,  one  member 
of  each  group  acting  as  foreman.  The  foreman  is  held 
responsible  for  the  quality  as  well  as  the  quantity  of 
the  output  of  his  plant,  must  see  that  the  machinery  is 
left  in  perfect  condition,  and  that  the  factory  is  kept 
clean. 

In  these  days,  when  manufacturers  are  turning  to 
technically  trained  men  to  fill  positions  of  respon- 


376124 


Vi  PREFACE  TO  SECOND  EDITION 

sibility  in  their  plants,  it  behooves  the  technical  schools 
to  make  the  training  of  young  men  as  broad  as  pos- 
sible along  applied  lines,  for  the  man  with  a  knowledge 
of  manufacturing  operations  and  factory  equipment  will 
have  a  decided  advantage  over  the  one  with  a  purely 
scientific  education. 

Inasmuch  as  this  book  is  a  plea  for  a  more  widespread 
introduction  of  Industrial  Chemistry  into  technical  schools, 
the  author  would  greatly  appreciate  any  suggestions  that 
might  make  the  book  more  completely  serve  its  purpose. 
The  text  presupposes  a  certain  knowledge  of  chemistry 
and  purposely  leaves  many  of  the  minor  details  to  be 
worked  out  by  the  student.  To  the  instructor  also  is 
given  great  latitude  that  he  may  exercise  his  own  origi- 
nality the  more  freely. 

ALLEN  ROGERS. 
PRATT  INSTITUTE, 

BROOKLYN,  AUGUST,  1917. 


TABLE   OF   CONTENTS 


PAG  a 

PREFACE v 

I    GENERAL  PROCESS i 

II    INORGANIC  PREPARATIONS 16 

III  ORGANIC  PREPARATIONS 29 

IV  DYEING  OF  TEXTILE  FIBERS 68 

V    PIGMENTS  AND  LAKES 98 

VI    DRIERS,  VARNISHES,  PAINTS  AND  STAINS    .    .    .  «.    .    .108 

VII    SOAP  AND  ALLIED  PRODUCTS 128 

VIII    LEATHER  MANUFACTURE I41 

IX    WOOD  FIBER,  PULP  AND  PAPER     ,    . 189 

X    USEFUL  DATA   .     .  •  .  iQ5 


vu 


LABORATORY   GUIDE    OF 
INDUSTRIAL  CHEMISTRY 


CHAPTER  I 
GENERAL   PROCESSES 

1.  Crushing.     In  the  preparation  of  chemical  products, 
one   of   the   most   important   features   is   the   converting 
of  raw  material  to  a  state  of  fine  division.     This  may 
be   accomplished  in   several  ways,   depending  upon   the 
nature  of  the  raw  material. 

For  fairly  hard  material  the  laboratory  crusher  (Fig.  i) 
is  usually  employed.  In  its  simplest  form  the  crusher 
consists  of  a  steel  plate  against  which  a  corresponding 
steel  jaw  works  on  a  cam,  giving  a  rolling  motion. 
This  form  of  crusher  will  be  found  in  practically  any 
well  equipped  laboratory  and  can  be  purchased  at  a 
nominal  cost.  In  the  manufacture  of  such  chemicals  as 
magnesium  sulphate,  barium  chloride,  or  similar  products, 
the  ore  should  first  be  brought  to  a  state  of  fine  division 
in  this  form  of  crusher. 

2.  Grinding.     It  is  often  necessary  to  reduce  an  ore 
or  other  raw  material  to  a  much  finer  state  of  division 
than  is  possible  with  the  jaw  crusher;    for  such  material 
some    other    form   of  grinding  machine   must  be   used. 


I   V  tj 


2       LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

The  simplest  and  most  common  form  of  grinding  apparatus 
consists  of  two  hardened  steel  plates,  one  of  which  rotates 
rapidly  over  the  other  in  a  manner  somewhat  similar  to 


FIG.  i. 


FIG.  2. 


the  ordinary  grinding  in  a  mortar.  There  are  several 
types  of  such  machines  on  the  market,  but,  as  they 
all  work  on  the  same  principle,  no  special  recommenda- 
tion is  needed  for  any  particular  one.  A  common 
form  of  laboratory  mill  is  shown  in  Fig.  2.  It  should 


GENERAL  PROCESSES  3 

always  be  borne  in  mind  that  the  finer  the  material  is 
ground,  the  more  rapid  and  complete  will  be  the  action 
when  chemical  treatment  takes  place. 

3.  Lixiviation.  This  process  effects  a  separation  of 
water-soluble  material  from  insoluble  or  less  soluble  ma- 
terial. The  material  to  be  lixiviated  is  placed  in  open 
tanks  provided  with  perforated  false  bottoms,  and  the 
necessary  amount  of  water  added.  The  tanks  are  some- 
times equipped  with  closed  steam  coils  for  heating.  They 


FIG.  3. 

are  usually  arranged  in  series,  constituting  what  is  called 
a  battery  (Fig.  3).  The  solution  containing  the  soluble 
material  is  drawn  off  from  the  false  bottom  of  one 
tank  into  the  top  of  the  next,  thus  coming  into  contact 
each  time  with  fresher  material  and  increasing  in  strength, 
while  fresh  water,  added  to  the  tank  after  each  succes- 
sive drawing  off,  comes  in  contact  with  the  partly  ex- 
hausted material,  dissolving  out  still  more  of  the  soluble 
portion. 

4.  Decantation.     This  process  is  commonly  used  when 
the  preparation  of  chemical  products  is  accompanied  by 


4       LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

the  formation  of  a  certain  amount  of  insoluble  material. 
The  precipitate,  or  insoluble  residue,  is  allowed  to  settle 
and  the  clear,  supernatant  liquid  removed  either  by  means 
of  a  siphon  or  by  pouring  over  the  side  of  the  vessel. 

5.  Washing.     In  many  instances,   it  is  necessary   to 
remove  the  excess  of  impurities  from  a  product,  and,  where 
these  impurities  are  of  a  soluble  nature,   care  must  be 
taken  to  remove  them  as  completely  as  possible.     The 
simplest  method  of  washing   large   quantities  of  material 
is  to  stir  the  insoluble  residue  with  sufficient  water,  allow 
it  to  settle,  and  then  remove  the  solution  by  decantation, 
continuing  the  operation  until  washing  is  complete. 

6.  Concentration.  By  concentration  is  meant  the  process 
by  which  a  material  is  converted  into  a  higher  degree  of 
compactness.     For  most  chemical  purposes,  this  is  brought 
about   by   removing   a   certain   amount   of   the   solvent, 
usually  water.     There  are  cases,  however,  where  concen- 
tration may  apply  to  mixtures  of  solids,  the  more  highly 
purified  material  being  known  as  concentrates. 

7.  Evaporation.     This  process  consists  in  removing  a 
solvent  from   a  soluble  material.     The   solvent  in  most 
cases  is  water,  and  evaporation  may  be  brought  about 
in  a  number  of  ways. 

(a)  Spontaneous   Evaporation.     The  liquid  is  exposed 
in  shallow  pans  to  the  direct  action  of  the  wind  and  sun, 
as,  for  instance,  in  the  production  of  common  salt    from 
brine. 

(b)  Evaporation  by  Direct  Heat.     This  takes  place  when 
the  hot  gases  from  a  fire  or  burner  are  allowed  to  play 
upon  the  bottom  of  the  containing  vessel. 

(c)  Evaporation  by  Indirect  Heat.     This  process  is  car- 
ried out  either  by  conducting  steam  through  closed  coils 


GENERAL  PROCESSES 


contained  in  a  suitable  vessel,  or  by  means  of  the  steam- 
jacketed  kettle,  where  the  temperature  is  regulated  by 
the  steam  pressure.  The 
steam-jacketed  kettle  (Fig. 
4)  is  generally  used.  The 
solution  is  placed  in  the 
kettle  and  the  drain  opened. 
Then  the  outlet  is  also 
opened,  and  the  inlet  valve 
given  a  half-turn.  As  the 
steam  comes  in  contact  with 
the  cold  surface,  it  con-  FlG 

denses  and  passes  off  through 

the  drain.     As  soon  as  live   steam   appears,   the   drip  is 
closed  and  more   steam   admitted  until  the  desired  tem- 


FIG.  5. 

perature    is    reached.      The    temperature    of   the    steam- 
jacketed  kettle  can  be  rasied  by  partly  closing  the  exhaust. 
(d)  Evaporation  under   Reduced   Pressure.     By  means 


6       LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

of  any  of  the  various  forms  (Fig.  5)  of  vacuum  pans  now 
on  the  market,  the  time  necessary  for  evaporation  may  be 
shortened  and  a  saving  in  heat  effected. 

8.  Roasting.  In  the  manufacture  of  certain  products, 
an  elevated  temperature  becomes  necessary.  This  is 
furnished  by  several  forms  of  furnaces,  most  common 
among  which  are  the  reverberatory  furnace,  muffle  fur- 
nace, revolving  furnace  (Fig.  6),  and  kiln.  The  process 
is  also  sometimes  called  calcination.  The  object  of  roasting 


FIG.  6. 

or  calcination  is  usually  to  remove  a  volatile  constituent 
in  the  product. 

9.  Crystallization.  In  the  preparation  of  chemical 
salts,  crystallization  is  resorted  to  in  order  that  the  material 
may  be  separated  in  a  pure  condition.  When  a  salt  is  dis- 
solved in  water,  a  point  is  reached  where  no  more  of  the 
material  will  go  into  solution.  If,  at  this  point,  the 
solution  is  concentrated,  until  a  slight  scum  appears  on 
the  surface,  and  then  allowed  to  cool,  it  will  be  noticed 
that  more  or  less  regular  crystalline  todies  form  as  the 
temperature  falls,  care  having  been  taken  not  to  disturb 
the  vessel  during  this  time.  The  crystals  thus  separated 


GENERAL  PROCESSES  7 

are  usually  a  very  pure  form  of  the  salt.  By  further 
evaporation  cr  concentration  of  the  mother  liquor,  more 
crystals  will  result,  less  pure,  however,  than  the  first  crop. 
By  means  of  the  process  of  crystallization  it  is  usually 
possible  to  separate  a  mixture  of  two  or  more  soluble 
compounds. 

10.  Filtration.    An  insoluble  substance,  suspended  in 


FIG.  7. 


a  liquid,  can  be  removed  by  filtration,  i.e.,  by  passing 
the  liquid  through  a  more  or  less  porous  material.  On 
a  very  small  scale,  the  ordinary  filter  paper  and  funnel 
may  be  used,  in  which  case  the  insoluble  portion  remains 
on  the  paper  in  the  funnel,  while  the  soluble  portion  passes 
through.  On  a  larger  scale,  the  same  principle  operates 
with  the  bag  filter.  This  can  be  readily  made  by  tacking 
a  fairly  heavy  muslin  over  a  wooden  frame  (Fig.  7), 


8       LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 


the     size    depending     upon     the    requirements     of     the 
operator. 

11.  Vacuum  Filter.  For  some  coarse  materials  the 
vacuum  filter  gives  very  satisfactory  results.  In  its 
simplest  form,  this  filter  (Fig.  8)  comprises  a  lower  vessel 
arranged  for  attachment  to  a  vacuum  pump,  and  an 
upper  vessel  fitted  tightly  to  the  lower  portion.  The 


FIG.  9. 

upper  vessel  is  provided  with  a  perforated  bottom  upon 
which  may  be  spread  filter  paper,  canvas,  sand,  or  asbestos. 
12.  Filter  Press.  For  handling  large  volumes  of  liquid, 
the  filter  press  method  is  most  common.  Many  types  of 
filter  presses  are  on  the  market,  all  of  which  work  upon 
practically  the  same  principle.  A  plate  is  so  arranged 
that  it  may  be  covered  with  canvas  or  bolting  cloth, 
and  the  material  to  be  filtered  is  forced  against  this  plate 
under  pressure.  A  simple  laboratory  press  is  shown  in 
Fig.  9. 


GENERAL  PROCESSES 


9 


13.  Drying.  Chemical  salts,  after  crystallization,  carry 
with  them  more  or  less  of  the  mother  liquor.  In  removing 
this,  the  centrifugal  machine  has  been  found  to  give 
the  best  results.  This  machine  (Fig.  10)  consists  of  a 
basket  suspended  on  a  shaft  in  such  a  manner  that  it 
may  be  rotated  at  very  high  speed.  The  crystals,  being 
thrown  against  the  walls  of  the  receptacle,  are  retained, 


FIG.  10. 

while  the  mother  liquor  passes  through  the  perforations. 
For  materials  that  cannot  be  dried  in  the  centrifuge 
other  machines  must  be  employed.  Among  these  should 
be  mentioned  the  drying  oven  and  the  vacuum  dryer. 
The  drying  oven  is  essentially  a  chamber  heated  by  means 
of  steam;  while  the  vacuum  dryer  (Fig.  n)  is  provided 
with  air-tight  doors  and  a  vacuum  connection. 

14.  Sublimation.     This  occurs  when  a  substance  passes 


10      LABORATORY   GUIDE  OF  INDUSTRIAL   CHEMISTRY 

from  a  solid  to  a  vapor  and  then  back  again  to  a  solid 
without  passing  through  the  intermediate  liquid  stage, 
as  for  instance,  when  crude  naphthalene  is  heated  in  an 
iron  kettle  over  a  low  flame,  or,  better,  on  asbestos.  The 
naphthalene  vaporizes  and  may  be  condensed  by  placing 
a  cone  over  the  top  of  the  kettle,  leaving  a  very  small 
opening  in  the  top  for  escaping  gases.  The  cone  may  be 
made  of  sheet  iron  or  even  of  heavy  cardboard.  A  piece 


FIG.  ii. 

of  muslin  or  filter  paper  may  also  be  stretched  over  the 
kettle  to  serve  as  a  filter  and  retain  any  liquid  that  may 
be  given  off. 

15.  Distillation.  There  are  many  forms  of  apparatus 
employed  for  fractional  distillation.  The  one  illustrated 
in  Fig.  12  is  very  satisfactory  for  laboratory  work.  This 
can  be  obtained  from  any  copper  maker.  It  may  be  heated 
by  steam-coils,  steam-jacket,  or  by  open  fire,  according 
to  the  nature  of  the  product  being  distilled. 


GENERAL  PROCESSES 


11 


16.  Density.  By  density  or  specific  gravity  of  a 
liquid  is  meant  its  relative  weight  as  compared  to  the 
weight  of  an  equal  volume  of  water  at  a  definite  tempera- 
ture. The  determination  of  specific  gravity  is  one  of 
the  most  frequent  operations  in  chemical  work.  For  all 
practical  purposes  the  test  may  be  made  with  the  hydrom- 


STILL 


eter,  but  for  very  exact  results  the  specific  gravity  bottle 
(pyknometer) ,  or  the  Westphal  balance  is  employed. 

Three  systems  of  hydrometer  scales  are  in  common 
use,  as  well  as  a  great  many  special  ones  intended  for  de- 
termining the  density  of  a  particular  substance  in  a  liquid; 
the  principle,  however,  is  the  same  in  each  case.  These 
instruments  are  usually  of  glass,  having  a  bulb  weighted 
at  the  lower  end,  and  drawn  out  at  the  upper  end  into  a 


12    LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

long  slender  tube  carrying  a  scale.  The  graduations  on 
the  scale  are  at  the  top  and  read  downward,  the  largest 
number  being  at  the  bottom,  except  in  one  instance — 
that  of  Baume's  scale  for  liquids  lighter  than  water,  where 
it  is  the  reverse. 

When  the  hydrometer  is  placed  in  a  liquid  it  sinks 
sufficiently  to  displace  a  volume  equal  in  weight  to  the 
weight  of  the  instrument  and  floats  in  an  upright  position. 

17.  The  Direct  Specific  Gravity   Hydrometer.    This  in- 
strument is  so  constructed  that  the  reading  of  the  scale 
shows  the  density  of  a  liquid  as  compared  with  water 
at  15*5°  C.    The  point  to  which  it  sinks  in  pure  water 
is  marked  i.ooo. 

These  hydrometers  are  usually  in  a  set  of  four.  The 
first  spindle  is  graduated  from  .700  to  i.ooo  and  is  for 
liquids  lighter  than  water,  the  i.ooo  being  at  the  bottom; 
whereas  the  remainder  of  the  set  is  for  liquids  heavier 
than  water,  with  the  smaller  number  at  the  top  starting 
with  i.ooo. 

Practical  use  is  made  of  the  density  of  solutions  for 
determining  the  weight  of  given  volumes. 

18.  Barkometer.    This  is  a  special  form  of  direct  specific 
gravity  hydrometer  in  which  only  the  numerals   to   the 
right  of  the  decimal  are  used.     Thus,  1.030  specific  gravity 
would  be  30°  on  the  Barkometer,  and  1.125  specific  gravity 
would  be  125°  Bk.     This  instrument  is  in  common  use 
in  the  tanning  industry. 

19.  TwaddelVs  Hydrometer.    This  is  also  a  direct-read- 
ing instrument.     The  set  consists  of  a  series  of  spindles 
(usually  six)  having  graduations  from  o°  to  174°.     The 
reading  for  water  at  15.5°  is  taken  as  o°,  and  each  rise  of 
0.005  in  sp.  gr.  is  recorded  on  the  scale  as  one  additional 


GENERAL  PROCESSES  13 

division.  Thus,  10°  Twaddell  becomes  1.050  sp.  gr.  The 
density  by  this  means  is  recorded  as  10°  Tw. 

Twaddell  readings  are  readily  converted  into  specific 
gravity  in  the  following  manner : 

Multiply  the  reading  by  .005  and  add  i.ooo  to  the 
product.  Thus,  15°  Tw.  =1.075  SP-  gr- 

;i.ooo  +  (i5X.oo5)  =1.075). 

In  the  reverse  order,  specific  gravity  may  be  con- 
verted into  Twaddell.  Thus,  1.150  sp.  gr.  becomes 

O     TT* 

30    Tw. 

((1.150-1.000)  ^.005  =30). 

That  is,  from  the  specific  gravity  subtract  i.ooo  and 
divide  by  .005. 

This  is  the  most  convenient  hydrometer  for  factory 
or  laboratory  use.  It  is,  however,  not  adapted  to  liquids 
lighter  than  water. 

20.  Baume's  Hydrometer.  This  is  a  very  unscientific 
instrument,  but  is  largely  used  in  technical  work.  Its 
readings  have  no  direct  relation  to  specific  gravity. 
Baume  dissolved  15  parts  of  pure  salt  in  85  parts  of  pure 
water  at  12.5°  C.  The  point  to  which  his  instrument 
sank  was  marked  15;  the  point  to  which  it  sank  in  pure 
water  was  marked  o.  The  distance  between  these  points 
was  divided  into  fifteen  equal  parts.  This  produced  an 
instrument  for  liquids  heavier  than  water. 

For  liquids  lighter  than  water,  the  point  to  which  the 
instrument  sank  in  a  10  per  cent  solution  of  salt"  was 
marked  o,  and  that  to  which  it  sank  in  water  was  marked 
10 ;  the  distance  between  these  points  was  divided  into 
ten  equal  parts,  and  this  graduation  continued  the 


14      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

entire  length  of  the  spindle.  Thus  the  lighter  the  gravity 
of  the  liquid  tested,  the  greater  numerically  is  the  reading 
of  the  scale.  For  instance,  a  liquid  reading  70°  Be.  is 
of  less  density  than  one  at  50°  Be.,  which,  in  turn,  is 
lighter  than  water  at  10°  Be. 

The  conversion  of  American  Standard  Baume  readings 
to  specific  gravity  is  usually  accomplished  by  reference 
to  tables,  but  may  be  worked  out  as  follows: 

Sp.  err.  =  -       -r,  x    (for   liquids   heavier   than  water   at 
144.3  -Be. 

15°  C.) 


Sp.  gr.  =—        D^  (f°r  liquids  lighter  than  water  at  17.5°  C.) 

There  is  still  another  form  of  Baume  which  is  in  quite 
common  use,  the  so-called  Rational  Scale  Baume  instru- 
ment (Kolb's),  which  indicates  zero  in  pure  water  at 
15°  C.,  and  66  in  sulphuric  acid  of  sp.  gr.  1.842  at  15°  C. 

21.  The  Pyknometer.  This  consists  of  a  small  bottle, 
having  ground  into  its  neck  a  capillary  stopper  provided 
with  a  reservoir.  The  bottle  is  filled  with  the  liquid  to 
be  tested,  and  the  stopper  loosely  inserted.  When  the 
bottle  and  contents  have  reached  the  normal  temperature, 
the  excess  of  liquid  is  removed  by  means  of  filter  paper 
until  the  level  of  the  liquid  reaches  the  graduation  mark. 
The  stopper  is  tightly  inserted,  and,  after  cleaning  and 
drying,  the  instrument  is  weighed. 

The  density  of  the  liquid  is  ascertained  by  the  following: 

_  Weight  of  bottle  and  liquid  —weight  of  bottle 
Weight  of  bottle  and  water  —weight  of  bottle' 


GENERAL  PROCESSES  15 

Or, 

Weight  of  liquid 
Sp.  gr.  =; 


Weight  of  equal  volume  of  water 

22.  Westphal  Balance.  This  is  a  special  form  of  bal- 
ance for  determining  the  density  of  liquids.  A  glass 
plummet  of  known  weight  and  volume  is  suspended  from 
the  beam  by  a  fine  platinum  wire,  and  is  submerged  in 
the  liquid  to  be  tested.  The  weight  which  the  plummet 
loses  is  the  weight  of  the  liquid  displaced.  This  loss  can 
be  determined  by  using  a  set  of  riders  graduated  to  read 
directly  into  specific  gravity. 

In  all  determinations  of  density,  the  question  of  tem- 
perature is  an  important  factor,  and  all  corrections  should 
be  made  accordingly.  When  using  the  Twaddell  hydrom- 
eter for  commercial  purposes,  however,  the  addition  of 
i°  Tw.  for  each  20°  F.  above  60°  will  suffice. 


The  foregoing  general  processes  are  given  in  order 
that  the  student  may  have  some  idea  of  them  previous 
to  their  use  in  his  subsequent  work.  For  a  more  detailed 
description  of  the  apparatus  and  methods  employed,  he 
is  referred  to  the  Manual  of  Industrial  Chemistry,  or  to 
the  Elements  of  Industrial  Chemistry,  by  the  same  author. 


CHAPTER  II 
INORGANIC   PREPARATIONS 

23.  Aluminium  Sulphate  (A12(S04)  3- i8H20).  This  com- 
pound is  prepared  from  the  mineral  bauxite  (A1203-  2H2O). 
On  a  small  scale  porcelain  evaporating  dishes  may  be  used, 
but  on  a  larger,  laboratory  scale,  earthenware  crocks  are 
most  satisfactory.  They  may  be  heated  by  means  of 
live  steam  led  into  them  through  heavy  glass  tubes  con- 
nected with  the  steam  line. 

Weigh  out  loco  gms.  of  bauxite,  previously  ground  to 
a  fine  powder,  and  mix  it  to  a  paste  with  water.  To  the 
paste  add  slowly  and  with  constant  stirring  2300  gms.  of 
66°  Be.  sulphuric  acid.  Turn  on  the  steam  and  boil  con- 
tinuously until  all  frothing  ceases  and  the  mass  is  in  a 
state  of  quiet  ebullition.  To  complete  the  reaction  and 
insure  the  elimination  of  free  sulphuric  acid,  a  small  amount 
of  powdered  bauxite  is  cautiously  introduced  from  time  to 
time  until  no  more  frothing  occurs.  Add  10  volumes  of 
water  to  the  paste  and  bring  again  to  a  boil.  During  the 
process  of  boiling,  any  iron  that  may  be  present  is  in 
the  ferric  condition  and  must  be  reduced  to  the  ferrous 
state.  This  is  accomplished  by  adding  powdered  zinc 
equal  in  amount  to  0.5  per  cent  of  the  weight  of  the 
bauxite.  At  this  stage  of  the  operation  considerable 
suspended  matter  is  present,  which  is  allowed  to  settle 
by  standing  overnight.  When  the  solution  is  clear, 
decant  it  into  a  lead-lined  evaporating  pan  or  earthen- 

16 


INORGANIC   PREPARATIONS  17 

ware  dish,  concentrate  to  a  density  of  40°  Tw.,  and  allow 
to  cool.  Any  ferrous  sulphate  present  will  crystallize, 
and,  after  removing  it,  concentrate  the  liquor  again  until 
a  test  sample  solidifies  upon  cooling.  It  is  then  allowed 
to  cool  and  the  solid  mass  broken  into  lumps. 

Write  the  reactions  involved. 

Calculate  the  theoretical  yield. 

Weigh  the  product  obtained. 

Estimate  the  percentage  yield. 

Estimate  the  manufacturing  cost. 

In  all  manufacturing  operations,  the  main  object  is 
to  make  a  profit  on  the  goods.  It  is  necessary,  therefore, 
to  have  a  pretty  clear  idea  of  the  cost  of  production. 
The  following  example  will  serve  as  a  guide  to  this  and 
other  problems. 

(In  making  estimates,  use  grams  as  if  they  were  pounds.) 

Bauxite,  1000  Ibs.  at  ^  ^ $  5 .00 

Sulphuric  acid,  2300  Ibs.  at  i  £. 23 .  oo 

Incoming  freight,  3300  Ibs.  at  6  ^.  per  100       i  .98 
Outgoing   freight,   4970   Ibs.    (theoretical 

yield)  at  6  £.  per  100 2 . 98 

Containers,  4970  Ibs.  at  15  £.  per  loo-lb. 

unit 7 . 50 

$40 . 46 

Fixed  and  overhead  charges,  20  per  cent 

of  cost  of  production 8 . 09 

Total  cost  of  production $48 . 55 

Cost  per  pound,  $48 . 55  -^4970  Ibs o .  98 

24.  Potash  Alum  (K2S04-A12(S04)3'  24H2O).  This 
compound  is  produced  by  dissolving  the  molecular  equiv- 


18      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

alents  of  aluminium  sulphate  and  potassium  sulphate  in 
the  necessary  quantity  of  water  and  concentrating  the 
resulting  solution  until  crystals  appear  on  the  edge  of 
the  evaporating  dish.  The  liquor  is  then  transferred  to  a 
crystallizing  tank  and  not  disturbed  until  a  full  crop 
of  crystals  has  been  obtained.  After  the  removal  the 
crystals,  the  mother  liquor  may  again  be  concentrated  for 
a  further  yield. 

For  crystallizing  on  a  small  scale,  vessels  of  glass  may 
be  used,  but,  on  a  larger  scale,  square  earthenware  tanks 
are  best  fitted  for  the  purpose.  On  a  commercial  scale, 
lead-lined  wooden  tanks  are  preferred.  To  aid  crystal- 
lization, strips  of  lead  attached  to  wooden  sticks  may 
be  suspended  in  the  tanks. 

Write  the  reactions  involved. 

Estimate  the  theoretical  yield. 

Weigh  the  resulting  product. 

Calculate  the  percentage  yield. 

Estimate  the  cost  on  theoretical  yield. 

Estimate  the  cost  on  actual  yield. 

25.  Barium  Chloride  (BaCl2-2H2O).  This  chemical  is 
prepared  on  a  commercial  scale  from  barytes  (BaS04). 
The  mineral  is  ground  to  a  fine  powder  and  heated  with 
carbon  to  reduce  it  to  the  sulphide.  The  lixiviated  mass 
is  treated  with  sodium  carbonate  to  convert  it  into  the 
carbonate,  and  then  with  hydrochloric  acid  to  change  this 
carbonate  into  the  chloride. 

The  necessary  apparatus  comprises  a  furnace,  tanks, 
vacuum  filter,  evaporating  dishes,  crystallizing  tanks,  and 
a  centrifugal  machine. 

Intimately  mix  1000  gms.  of  powdered  barytes  with 
300  gms.  of  powdered  charcoal  and  transfer  the  mixture 


INORGANIC  PREPARATIONS  19 

to  the  floor  of  a  muffle  furnace.  Heat  the  muffle  and 
contents  to  a  bright  red  and  hold  the  temperature  at  this 
point  until  a  test  portion  shows  that  practically  all  of 
the  sulphate  has  been  reduced.  To  derive  the  full  benefit 
from  the  reducing  action  of  the  carbon,  it  is  neces- 
sary, during  the  .heating,  to  prevent  the  charge  from 
coming  into  contact  with  the  air.  The  door,  however, 
must  be  opened  from  time  to  time  and  the  mass  well 
stirred. 

On  completion  of  the  heating,  the  mass  is  allowed  to 
cool  and  is  then  transferred  to  a  lo-gallon  earthenware 
vessel  containing  5  gallons  of  water.  Live  steam  is  now 
led  into  the  jar  and  the  contents  boiled  for  about  one 
hour.  After  standing  overnight  to  allow  insoluble  matter 
to  settle,  the  clear  solution  is  decanted  into  another  10- 
gallon  jar  or  precipitating  tank,  and  sufficient  sodium  car- 
bonate in  solution  added  to  throw  down  the  barium  as  car- 
bonate. In  order  to  ascerten  the  exact  amount  of  sodium 
carbonate  to  add,  a  rapid  determination  of  barium  as 
sulphate  should  be  made.  The  precipitated  barium  car- 
bonate is  allowed  to  settle,  and  the  clear  solution,  con- 
taining sodium  sulphide,  is  evaporated  to  dryness  in  order 
to  obtain  this  chemical  as  a  by-product. 

The  barium  carbonate  is  washed  by  decantation  until 
free  from  sulphide  and  then  dissolved  by  the  addition 
of  the  calculated  amount  of  hydrochloric  acid  diluted  with 
three  parts  of  water.  To  the  solution  of  barium  chloride 
a  small  excess  of  barium  carbonate  is  added,  and  the 
whole  boiled  for  about  half  an  hour  to  throw  out  any 
impurity  of  iron  that  may  be  present.  After  again  settling, 
the  clear  solution  is  decanted  to  an  evaporating  dish  and 
concentrated  until  crystals  appear  on  the  edges  of  the 


20    LABORATORY  GUIDE  OF  INDUSTRIAL   CHEMISTRY 

dish,  when  it  is  transferred  to  the  crystallizing  tank. 
The  residue  from  the  above  is  thrown  on  to  the  vacuum 
filter,  and  the  filtrate  added  to  the  solution  being  con- 
centrated. 

The  barium  chloride,  on  removal  from  the  tank,  is 
placed  in  the  centrifugal  machine  and  whizzed  for  five 
minutes  to  remove  adhering  liquor.  The  mother  liquor 
is  further  concentrated  for  another  yield. 

Write  the  reactions  involved. 

Estimate  the  theoretical  yield. 

Weigh  the  resulting  product. 

Calculate  the  percentage  yield. 

Estimate  the  cost  on  theoretical  yield. 

Estimate  the  cost  on  actual  yield. 

26.  Chromium  Acetate  (C^f^HaC^e).  To  1000  gms. 
of  sodium  dichromate,  dissolved  in  10  liters  of  water,  add 
500  gms.  of  concentrated  sulphuric  and  then,  very  slowly, 
a  concentrated  solution  of  noo  gms.  of  sodium  bisul- 
phite. The  action  of  the  bisulphite  is  to  change  the 
chromium  from  the  acid  to  the  basic  condition,  the  end 
point  being  determined  when  the  yellow  color  changes  to 
green.  The  product  of  this  reaction  is  the  basic  sul- 
phate of  chromium  (Cr2 (OH)  2(804)2).  Next  dissolve  800 
gms.  of  soda  ash  in  as  little  water  as  possible  and  add,  a 
small  portion  at  a  time,  to  the  chromium  solution.  The 
chromium  hydroxide  formed  is  allowed  to  settle,  and  the 
clear  supernatant  liquid  decanted  and  evaporated  for  the 
yield  of  sodium  sulphate  as  a  by-product. 

The  chromium  hydroxide,  washed  free  from  sulphates 
by  decantation,  is  treated  with  the  calculated  quantity 
of  commercial  acetic  acid  and  evaporated  to  a  concen- 
tration of  90°  Tw. 


INORGANIC   PREPARATIONS  21 

Write  the  reactions  involved. 

Estimate  the  theoretical  yield  of  pure  salt. 

Weigh  the  resulting  product. 

Calculate  actual  percentage  yield. 

Estimate  the  cost  of  manufacture. 

27.  Sodium  Bichromate  (Na2Cr207-2H20).     Mix  inti- 
mately 980  gms.  of  lime,  960  gms.  of  soda  ash,  and  1000 
gms.  of  very  finely  powdered  chromite.     Convey  the  mix- 
ture to  the  floor  of  a  reverberatory  furnace  and  heat  with 
the  oxidizing  flame  at  a  bright  red  heat  for  a  period  of 
from    three    to    four   hours.     The   resulting   mass,    when 
cooled,  is  pulverized  and  extracted  with  hot  water  until 
practically  no  more  color  is  shown  in  the  wash  water. 
The    solution    and    washings    are    then    concentrated    to 
35°  Be.     To  this  hot  concentrated  solution,  sulphuric  acid 
is  added  until  the  starch  iodine  paper  test  shows  the 
presence  of  free  chromic  acid.     The  solution  is  then  fur- 
ther concentrated  until  crystals  of  sodium  sulphate  separate. 
These  are  removed  by  rapid  filtration  in  the  centrifugal 
machine   and   washed   with   a   small   quantity   of   water. 
The  mother  liquor  and  wash  water  from  the  sodium  sul- 
phate is  then  slowly  evaporated  with  constant  stirring. 
The  crystals  of  sodium  dichromate  obtained  are  whizzed 
to  remove  adhering  liquor. 

Write  reactions  involved. 
Estimate  theoretical  yield. 
Weigh  the  resulting  product. 
Calculate  the  percentage  yield. 
Estimate  cost  of  theoretical  yield. 
Estimate  the  cost  of  actual  yield. 

28.  Hydrogen    Peroxide    (H^C^).     Mix    500    gms.    of 
barium  peroxide  to  a  thin  cream  with  water  and  slowly 


22      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

add  the  calculated  quantity  of  phosphoric  acid.  The 
temperature  should  not  rise  above  15°  C.  When  all  of 
the  barium  has  been  precipitated  as  phosphates,  it  is 
allowed  to  settle  and  the  solution  of  H2O2  removed  by 
decantation. 

29.  Ferrous  Sulphate  (FeS04'7H2O).     This  chemical, 
on  a  commercial  scale,  is  usually  manufactured  in  con- 
nection with  foundry  practice.     It  is  obtained  from  the 
pickle  liquor  used  for  cleaning  castings.     In  the  laboratory, 
the  most  satisfactory  method  is  to  use  a  wooden  tub  or 
oak  barrel,  placing  therein  a  quantity  of  scrap  iron  or 
iron   turnings.     Cover   the  iron  with  water   and   add   a 
small    quantity    of    commercial    sulphuric    acid,    diluting 
from  time  to  time  with  more  water  when  crystallization 
is  indicated.     When  the  liquor  is  sufficiently  concentrated, 
it  is  removed,  filtered,  and  transferred  to  a  shallow  crys- 
tallizing vessel.     To  aid  crystallization,   suspend  narrow 
strips  of  clean  iron  in  the  solution.     Immediately  upon 
separation  from  solution,  the  crystals  should  be    dried  in 
the  centrifuge,  otherwise  rapid  oxidation  will  take  place. 

Write  the  reactions  involved  and  test  the  purity  of 
the  product  by  chemical  methods. 

30.  Ferrous  Ammonium  Sulphate   (FeS04(NH4)2SO4- 
6H20).     Dissolve  1400  gms.  of  ferrous  sulphate  and  664 
gms.  of  ammonium  sulphate  in  2000  cc.  of  water  separately, 
heating   to   60°   C.     Filter,   if  necessary.     Mix   the   two 
solutions,  concentrate  to  36°  Be.,  add  36  gms.  of  sulphuric 
acid,  and  allow  to  crystallize.     If,  on  cooling,  crystals  do 
not  form,  concentrate  the  liquor  until  a  scum    appears 
on  the  edge  of  the  evaporating  dish.     Cool  without  dis- 
turbing;   when    crystals    form,    remove    them,    and    dry 
in    the   centrifugal   machine.      The    mother   liquor   from 


INORGANIC  PREPARATIONS  23 

the    first   crop    of   crystals   is   evaporated   for   a   further 
yield. 

Test  the  purity  of  the  product  so  obtained. 

31.  Ferric    Sulphate    (Fe2(SO4)3).     Place    in    a    large 
evaporating  dish  about  1600  cc.  of  water,  add  330  cc.  of 
concentrated  sulphuric  acid,  and  heat  to  about  90°  C. 
To  the  diluted  acid  add  320  cc.  of  strong  nitric  acid  and 
stir  well.     Now  pulverize  3200  gms.  of  ferrous  sulphate 
and  add  this  slowly,  a  small  portion  at  a  time,  to  the  hot 
mixed  acid.     After  each  addition  of  ferrous  sulphate,  stir 
the  solution  well  and  add  the  subsequent  portions  only 
after  effervescence  has  ceased.     When  all  of  the  ferrous 
sulphate  has  been  used  up  and  no  more  fumes  appear, 
a  small  portion  should  be  tested  by  adding  a  small  quantity 
of  nitric  acid.     If,  by  an  evolution  of  red  fumes,  the  test 
portion  indicates  that  oxidation  has  not  been  complete, 
more    acid    should    be   added   to    the    reaction   product, 
until  the  evolution  of  fumes  ceases.     The  solution  thus 
formed   is   heated    to   boiling    until   all   fumes   of   nitric 
oxide  have  been  eliminated  and  the  solution  has  assumed 
a  deep,  reddish  brown  color.     Concentrate  the  liquor  to 
the  density  of   130°  Tw.   at  normal  temperature.     Pre- 
serve this  liquid  in  well-stoppered  bottles. 

Write  reactions  involved. 

Test  strength  of  material  by  analytical  means. 

Estimate  cost  of  finished  product. 

32.  Lead    Nitrate    (Pb(N03)2).     Place    1000   gms.    of 
litharge   in    an    earthenware   evaporating   dish   and   add 
sufficient  water  to  form  a  thin  cream.     To  this  cream, 
add  the  calculated  amount  of  nitric  acid  and  heat  to 
boiling.     When  all  of  the  litharge  has  dissolved,  filter  off 
the   insoluble  matter  and   concentrate   on   a   steam-bath 


24      LABORATORY   GUIDE  OF  INDUSTRIAL  CHEMISTRY 

until  crystals  appear  at  the  edge.  Remove  the  dish  from  the 
steam-bath  and  set  aside  overnight,  being  careful  not  to  dis- 
turb the  vessel  after  crystals  start  to  form.  Remove  the 
crystals  and  evaporate  the  mother  liquor  for  a  further  yield. 

Write  the  reactions  involved. 

Calculate  the  theoretical  yield. 

Determine  actual  yield. 

Test  salt  for  purity. 

33.  Magnesium  Sulphate  (MgS04-7H20).     Having  de- 
termined  the  presence  of  magnesium  in  magnesite   and 
the  strength  of  the  sulphuric  acid,  estimate  the  quantity 
of  each  necessary  to  produce  4000  gms.  of  salt. 

Write  equations  and  calculations. 

Mix  the  magnesite  with  about  twice  its  quantity  by 
weight  of  water;  slowly  add  the  sulphuric  acid,  and  heat 
on  a  steam-bath  until  action  ceases.  If  acid  is  in  excess 
neutralize  with  powdered  magnesite,  heat  the  contents  of 
the  vessel  for  about  an  hour,  then  allow  the  suspended 
matter  to  settle,  and  filter  while  still  hot.  Evaporate  the 
filtrate  on  a  steam-bath  until  crystals  appear  along  the 
edges,  then  allow  to  remain  in  an  undisturbed  condition 
to  cool  and  crystallize.  The  crystals,  on  removal,  should 
be  dried  in  the  centrifuge,  and  the  mother  liquor  evap- 
orated for  a  further  yield'. 

Estimate  theoretical  yield. 

Determine  the  actual  yield. 

Estimate  cost  per  pound. 

34.  Potassium  Permanganate  (KMnO  4).   Ignite  a  quan- 
tity of  powdered  pyrolusite  at  red  heat  on  an  iron  plate, 
to  burn  out  any  carbonaceous  matter  it  may  contain. 
Dissolve  840  gms.  of  caustic  potash  in  1200  cc.  of  water, 
stir  in  420  gms.  of  potassium  chlorate,  and  heat  until 


INORGANIC  PREPARATIONS  25 

dissolved.  Then  mix  in  720  gms.  of  the  ignited  pyrolusite, 
evaporate  to  a  smooth,  thick  paste,  and  heat  to  redness 
in  an  iron  crucible,  adding  small  portions  at  a  time.  When 
thoroughly  hard,  let  the  crucible  cool,  and  break  out  the 
mass  with  a  chisel.  Then  boil  with  a  large  excess  of 
water,  passing  a  stream  of  carbon  dioxide  into  the  boiling 
solution  to  convert  any  hydroxide  into  carbonate.  The 
color  of  the  liquid  changes  from  green  to  violet  and  a 
dense  brown  precipitate  forms.  Filter  through  asbestos 
or  glass  wool  and  evaporate  the  nitrate  until  needle- 
like  crystals  appear  on  the  surface.  Allow  to  cool. 
Separate  the  crystals  and  evaporate  the  mother  liquor 
for  further  yield. 

35.  Sodium  Silicate  or  Water  Glass  (Na2Si03).     This 
compound  is  prepared  by  heating  a  mixture  of  sand  and 
sodium  carbonate  in  a  fire-clay  retort  or  iron  crucible 
until  the  product,  when  drawn  from  the  heating  vessel, 
gives  the  appearance  of  a  transparent  solid.     If  the  test 
sample,  when  cool,  gives  no  effervescence  with  dilute  acid, 
the  completion  of  the  process  is  indicated,  and  the  contents 
of  the  crucible  are  then  allowed  to  cool.     Dissolve  in  water, 
filter,  and  evaporate  to  a  syrupy  consistency. 

Write  reactions  involved. 
Determine  practical  yield. 

36.  Soda  Ash  (Na2C03).    Prepare  a  saturated  brine 
solution  by  dissolving  880  gms.   of  salt  in  3000  cc.   of 
water  at  15°  C.     To  this  brine  add  1000  cc.  of  ammonia 
(sp.  gr.  .910)  and  pass  in  carbon  dioxide  as  long  as  the 
gas  is  absorbed  and  a  precipitate  formed.     Care  should 
be  taken  to  keep  the  vessel  cool  and  to  use  a  large  delivery 
tube  in  order  to  prevent  clogging. 

The  precipitate  produced  is  sodium  bicarbonate  and 


26      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

should  be  filtered  by  suction  and  washed  with  a  little  cold 
water  to  remove  adhering  "salt.  It  is  then  dried  and  heated 
strongly  (do  not  fuse)  to  convert  the  bicarbonate  to  the 
carbonate. 

the  ammonia.    This  ammonia  may  be  absorbed  in  brine 
The  liquor  may  be  heated  with  milk  of  lime  to  recover 
and  the  process  repeated. 

37.  Disodium  Hydrogen  Phosphate  (Na2HP04-  i2H20). 
Into  a  lead-lined  tank  or  procelain  dish  introduce  5000  gms. 
of  bone-ash  and  mix  it  with  3880  gms.  of  sulphuric  acid 
(sp.  gr.  i. 80).     The  mixing  is  conducted  in  the  open  air 
or  hood.     Stir  well  and  allow  to  stand  overnight.     Lix- 
iviate the  mass  with  twice  its  volume  of  water  and  boil 
by  blowing  in  steam.     Filter  off  the  soluble  portion  and 
wash  the  residue  several  times  with  fresh  water.     Evaporate 
the  filtrate  and  washings  to  a  convenient  bulk  and  neu- 
tralize the  boiling  solution  with  a  concentrated  solution 
of  2750  gms.  of  soda  ash.     Filter  off  the  precipitate  of 
calcium  carbonate  and  evaporate  the  filtrate  until  the 
solution  has  a  density  of  25°  Tw.  at  60°  F.     The  crystals, 
which  separate  on  cooling,  should  be  dried  in  the  centrifugal 
and  bottled  as  soon  as  possible. 

Write  reactions. 
Estimate  theoretical  yield. 
Determine  practical  yield. 

38.  Sodium  Bisulphite  (NaHS03).     This  compound  is 
usually  placed  on  the  market  as  a  liquid  containing  33.3 
per  cent  of  the  salt.     It  is  prepared  by  passing  sulphur 
dioxide  into  a  solution  of  sodium  carbonate  until  com- 
pletely saturated.     The  SO2  may  be  easily  obtained  by 
burning  sulphur  in  a  small  furnace  (an  ordinary  muffle 
furnace  with  a  hole  bored  in  it)  and  drawing  the  gas  by 


INORGANIC  PREPARATIONS  27 

suction  through  the  soda  solution.     The  liquid  may  be 
placed  in  flasks  or  small  casks. 

Estimate  the  quantity  of  soda  ash,  water,  and  sulphur 
required  to  produce  10,000  gms.  of  the  product,  and  also 
the  cost  per  pound.  Write  the  reactions. 

39.  Sodium  Sulphite  (Na2SO  3- yH2O).     This  compound 
is  prepared  in  the  same  manner  as  sodium  bisulphite,  except 
that  the  solution  resulting  from  the  saturation  with  sul- 
phur dioxide  of   the   sodium   carbonate   solution  is   con- 
verted into  the  normal  salt  by  adding  the  same  amount 
of  sodium  carbonate  to  produce  the  original  sodium  bisul- 
phite solution  and  then  evaporating  on  a  steam-bath  until 
a  scum  appears.     It  is  then  set  aside  to  crystallize,  the 
mother  liquor  being  evaporated  for  a  further  yield. 

Write  the  reactions  involved. 
Calculate  the  theoretical  yield. 
Determine  the  practical  yield. 

40.  Sodium  Thiosulphate   (Na2S203'5H20).     Dissolve 
1000  gms.  of  sodium  sulphite  in  5  liters  of  water.     Place  in 
an   earthenware  vessel   provided  with  a  live-steam  con- 
nection.    To   the   solution   add  an   excess  of  flowers   of 
sulphur  and  boil  until  no  more  sulphur  is  dissolved.     Filter 
and  evaporate  to  the  point  of  crystallization.     Separate 
the  crystals  and  concentrate  the  mother  liquor  for  a  fur- 
ther yield. 

Write  the  reactions  involved. 
Estimate  the  theoretical  yield. 
Determine  the  practical  yield. 

41.  Sulphur   Monochloride    (S2Cl2).     Into   a    looo-cc. 
tubular  retort  place  500  gms.  of  sulphur  and  connect  the 
retort  with  a  Liebig  condenser  and  receiver.     Heat  the 
sulphur  until  melted  and  pass  in  a  current  of  chlorine 


28      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

in  such  a  manner  that  the  delivery  tube  comes  just  to  the 
top  of  the  melted  sulphur.  The  chlorine  may  be  gen- 
erated by  means  of  manganese  dioxide  and  hydrochloric 
acid,  or  by  the  electrolysis  of  a  salt  solution.  If  man- 
ganese dioxide  and  hydrochloric  acid  are  used,  the  solution 
of  manganese  chloride  should  be  concentrated  to  recover 
the  manganese  chloride  as  a  by-product.  In  the  prepa- 
ration of  sulphur  monochloride,  all  vessels  should  be 
perfectly  dry;  also  the  chlorine  gas  should  be  dried  by 
passing  it  over  sulphuric  acid. 

Write  the  reactions  involved. 

Calculate  the  theoretical  yield. 

Determine  the  actual  yield. 

42.  Ammonium  Paratungstate   ((NH^eWrC^^H^O). 
The  finely  ground  mineral,  Wolframite,  is  mixed  to  a 
thin  cream  with  nitric  acid  and  digested  on  a  steam-bath 
for  several  hours.     The  product  of  the  reaction  is  then 
evaporated  to  dryness  and  the  resulting  solid  treated  with 
ammonium  hydroxide.     When  all  of  the  yellow  tungstic 
oxide  has  dissolved,  the  insoluble  residue  is  filtered  off 
and  the  filtrate  evaporated  until  crystallization  is  indi- 
cated.    The  solution  is  then  set   aside   overnight.      The 
white  crystals  of  ammonium  paratungstate  being  separated, 
the  mother  liquor  is  concentrated  for  a  further  yield. 

Write  reactions  involved. 
Determine  the  practical  yield. 

43.  Zinc  Sulphate  (ZnSO4-7H2O).     Having  determined 
the  strength  of  the  sulphuric  acid  and  zinc  oxide,  estimate 
the  quantity  necessary  to  produce  5000  gms.  of  zinc  sul- 
phate and  work  out  the  method  of  procedure. 


CHAPTER  III 
ORGANIC  PREPARATIONS 

IN  all  of  the  following  preparations  the  student  is 
required  to  write  the  reactions  involved,  estimate  the 
theoretical  yield,  determine  the  percentage  yield,  and  test 
the  product  for  purity. 

44.  Alcohol  (C2H5OH).     Dissolve  500  gms.  of  glucose 
syrup  in  3  liters  of  water  at  33°  C.,  or  90°  F.,  and  add 
a  yeast  cake   that  has   been  made   into   a  cream  with 
water.     Place  the  flask  in  a  warm  place  and  allow  it  to 
stand  for  three  days,  or  until  fermentation  is  complete. 
Then  heat  the  contents  to  boiling  and  distill  off  about 
25  per  cent.     Determine  the  specific  gravity  of  the  dis- 
tillate, refer  to  table,  and  subject  to  redistillation  on  a  sand- 
bath,  repeating  the  operation,  if  necessary,  until  a  95  per 
cent  alcohol  is  obtained. 

45.  Ethyl  Bromide  (C2H5Br).     Into  a  i-liter,  round- 
bottom  distilling  flask    (Fig.    13)   introduce   20  gms.   of 
amorphous  phosphorus  and  120  gms.  of  absolute  alcohol. 
From  a  tap  funnel  slowly  add  120  gms.  of  bromine,  keeping 
the  flask  cool  by  immersion  in  cold  water.    Allow  the  flask 
and  contents  to  rest  for  two  hours  and  then  heat  gently 
on  the  water-bath  at  a  slowly  rising  temperature.    Shake 
the  distillate,  consisting  of  alcohol  and  ethyl  bromide, 
with  double  its  volume  of  water,  to  which  a  small  amount 
of  sodium  carbonate  has  been  added.    The  ethyl  bromide, 

29 


30      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

which  sinks  to  the  bottom,  is  drawn  off  and  shaken  several 
times  with  a  fresh  quantity  of  water.  It  is  then  com- 
pletely separated  from  the  water,  dehydrated  over  calcium 
chloride,  and  distilled  on  the  water-bath.  That  portion 
passing  over  between  36°-4o°  C.  is  pure  ethyl  bromide. 


FIG.  13. 

46.  Ether  ((C2H5)20).  Ether  is  extremely  inflam- 
mable. Take  care  that  no  flame  is  brought  near  it.  The 
reagents  used  are 

150  gms.    (80  cc.)  cone,  sulphuric  acid, 
85  gms.  (no  cc.)  absolute  alcohol. 

A  distilling  flask  Q-liter)  is  equipped  with  a  ther- 
mometer with  bulb  below  liquid  (Fig.  14),  and  a  separa- 
tory  funnel.  The  side  tube  of  the  distilling  flask  is  fitted 
by  a  cork  into  the  upper  end  of  a  long  condenser;  and  an 
adapter  at  the  lower  end  passes  through  the  neck  of  a 
flask  surrounded  by  ice.  The  sulphuric  acid  and  alcohol 


ORGANIC  PREPARATIONS 


31 


are  cautiously  mixed  in  the  distilling  flask,  which  is 
then  placed  upon  a  sand-bath  and  attached  to  the 
condenser.  The  mixture  is  heated  at  140°  C.  and  more 
alcohol  run  in  from  the  funnel  at  the  same  speed  the 
liquid  distills  (about  3  drops  a  second).  The  tem- 
perature must  be  kept  constant,  I4o°-i45°  C.  When 
about  150  cc.  of  alcohol  has  been  added  and  converted 
into  ether,  the  distillation  is  stopped.  In  addition  to 
ether,  the  receiver  now  contains  alcohol,  water,  and  sul- 


FIG.  14. 

phurous  acid.  The  liquid  is  poured  into  a  large  separating 
funnel  and  a  small  quantity  (30-40  cc.)  of  dilute  caustic 
soda 'added  and  well  shaken.  After  settling,  the  caustic 
soda  solution  is  drawn  off  below,  about  the  same  quantity 
of  a  strong  solution  of  common  salt  added,  and  the  process 
of  shaking  and  drawing  off  repeated.  The  ether,  which  is 
now  free  from  sulphuric  acid  and  from  most  of  the  alcohol, 
still  contains  water.  It  is,  therefore,  poured  into  a  large 
dry  distilling  flask  and  some  pieces  of  solid  calcium  chloride 
added.  It  is  allowed  to  stand  loosely  corked  overnight. 


32      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

The  distilling  flask  is  finally  attached  to  a  long  condenser 
and  heated  on  the  water-bath,  the  ether  passing  over  at 
about  40°  C. 

47.  Acetone  (CH3COCH3).  Place  200  gms.  of  calcium 
acetate,  known  commercially  as  gray  lime,  in  an  iron  retort 
(Fig.  15),  connected  to  a  Liebig  condenser.  Heat  the 
retort  and  contents  over  a  strong  flame  until  no  more 
distillate  is  obtained.  The  product  of  the  distillation  is 
impure  and  must  be  purified  by  treatment  with  a  small 
amount  of  oxalic  acid  and  redistilled.  That  portion 


FIG.  15. 

passing  over  at  56°  C.  is  collected  separately  as  pure 
acetone. 

48.  lodoform  (CHI3).  Dissolve  25  gms.  of  potassium 
iodide  in  500  cc.  of  water  and  add  5  gms.  of  acetone.  To 
this  mixture  add  through  a  drop  funnel  with  constant 
shaking  a  dilute  solution  of  sodium  hypochlorite  as  long 
as  a  precipitate  forms.  Allow  the  precipitate  to  settle. 
Decant  off  the  liquid,  wash  with  water  two  or  three  times, 
filter,  drain  thoroughly,  dry  on  filter  paper,  and  recrys- 
tallize  from  alcohol.  The  solution  of  sodium  hypochlorite 
used  in  this  experiment  may  be  made  by  precipitating 
all  the  calcium  in  a  solution  of  bleaching  powder  by  a 


ORGANIC  PREPARATIONS  33 

solution  of  sodium  carbonate.     A  slight  excess  of  sodium 
carbonate  will  not  interfere  with  the  reaction. 

49.  Chloroform  (CHC13).     (Trichlor methane).    A  large 
round  flask  (4  liters)  is  fitted  with  a  cork,  through  which 
passes  a  bent  tube  connecting  the  flask  with  a  long  con- 
denser and  receiver.     The  flask  is  placed  upon  a  large 
sand-bath.     Grind   200  gins,   of  fresh  bleaching  powder 
into  a  paste  with  400  cc.  of  water  and  rinse  it  into  the 
flask  with  400  cc.  more.     Add  40  gms.  (50  cc.)  of  acetone 
and  attach  the  flask  to  the  condenser.     Heat  cautiously 
until  a  reaction  sets  in,  indicated  by  the  frothing  of  the 
liquid.     Remove   the   flame  for  a  time,  until  the  reaction 
has  moderated;    finally  boil  the  contents  until  no  more 
chloroform  distills.     This  is  easily  determined  by  collecting 
the  distillate  in  a  test  tube  and  observing  if  any  drops 
of  heavy  liquid  are  present.     The  distillate  is  shaken  with 
dilute  caustic  soda  solution  in  a  separating  funnel,  and  the 
lower  layer  of  chloroform  run  into  a  distilling  flask.    A 
few  pieces  of  solid  calcium  chloride  are  added  and  left  until 
the  liquid  is  clear,  when  it  is  distilled  from  the  water-bath 
with  the  thermometer  inserted  into  the  neck  of  the  flask. 
The  portion  passing  over  at  62 °C.  is  pure  chloroform. 

50.  Acetic  Acid   (CH3COOH).     Dissolve  200  gms.  of 
calcium  acetate  in  the  least  possible  quantity  of  water, 
using  a  i5oo-cc.  round-bottom  flask.    Add  the  necessary 
quantity    of    commercial    hydrochloric    acid    to    combine 
with  the  calcium  present  and  distill  on  a  sand-bath,  con- 
necting the  flask  with  a  Liebig  condenser  as  in  Fig.  16. 
Redistill  the  distillate  and  collect  separately  that  portion 
passing  over  at  about  118°  C. 

61.  Acetyl    Chloride    (CH3COC1).     To    100    gms.    of 
glacial  acetic  acid  in  a  250-0:.   distilling  flask   add,   by 


34      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

means  of  a  dropping  funnel,  80  gms.  of  phosphorus  tri- 
chloride. The  distilling  flask  must  be  connected  with  a 
return  condenser  and  be  immersed  in  ice  water.  Shake 


FIG.  16. 


FIG.  17. 

the  flask  constantly  while  the  phosphorus  trichloride  is 
being  added.  After  ten  minutes  the  ice-water  may  be 
replaced  with  warm  water  and  heated  until  almost  all 
the  hydrochloric  acid  gas  has  been  evolved.  The  con- 


ORGANIC  PREPARATIONS 


35 


denser  may  then  be  turned  down  (Fig.  17)  and  the  acetyl 
chloride  rapidly  distilled  off.  The  acetyl  chloride  is  very 
easily  decomposed  by  moisture,  therefore  the  receiver 
must  be  protected  by  a  calcium  chloride  tube.  The 
acetyl  chloride  boiling  at  55 °  C.  may  be  purified  by  re- 
distillation. 

52.  Acetic  Anhydride  ((CH3CO)20).  Place  140  gms. 
of  fused  sodium  acetate  in  a  tubular  retort,  as  illustrated 
in  Fig.  1 8,  and  slowly  add  through  a  tap  funnel  50  gms. 
of  acetyl  chloride.  Thoroughly  mix  the  mass  with  a  rod 


FIG.  i 8. 

and  introduce  another  50  cc.  Heat  slowly  on  a  sand-bath 
until  all  of  the  anhydride  has  passed  over.  Then  purify 
the  distillate  by  redistillation  in  an  apparatus  like  that 
shown  under  acetyl  chloride.  Add  about  10  gms.  of 
fused  sodium  acetate  to  the  contents  of  the  flask  so  as 
to  take  up  any  uncombined  acetyl  chloride.  The  portion 
distilling  at  a  temperature  of  about  138°  C.  is  pure  acetic 
anhydride. 

53.  Amyl  Acetate  (CH3COOC5Hn).  Into  a  i-liter, 
side-neck  distilling  flask  place  200  gms.  of  fused  sodium 
acetate  and  to  it  slowly  add  a  mixture  of  215  gms.  of 
amyl  alcohol  with  250  gms.  of  sulphuric  acid.  Then  con- 


36      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

nect  the  distilling  flask  with  a  condenser  and  heat  the  con- 
tents on  the  sand-bath  until  no  more  distillate  is  obtained. 
The  impure  amyl  acetate  being  transferred  to  a  separating 
funnel  is  washed  with  water  and  then  with  dilute  sodium 
carbonate,  dehydrated,  and  redistilled.  The  portion  pass- 
ing over  between  i45°-i55°  C.  is  pure  amyl  acetate. 

54.  Monochloracetic  Acid  (CH2C1COOH).     Place  200 
gms.  of  glacial  acetic  acid  in  a  half-liter  retort,  provided 
with  reflux  condenser.     Heat  to  boiling  over  a  wire  gauze 
and  pass  in  dry  chlorine  gas  through   a   tube    that  just 
dips    below    the    surface    of    the    acid.      This    operation 
should   take   place   in   direct   sunlight   and   will   require 
about    five    hours    for    complete    conversion.     Provision 
should  be  made  for  absorbing  the  excess  of  chlorine,  and 
this  is  accomplished  by  connecting  the  end  of  the  con- 
denser with  a  drying  tower  containing  moist  soda  lime. 
When  the  reaction  is  complete,  the  resulting  product  is 
distilled  with  thermometer  dipping  in  the  liquid.     That 
portion  passing  off  up  to  130°  C.  consists  of  unchanged 
acetic  acid  and  is  rejected.     That  portion  boiling  between 
i3O°-i9o°    C.    consists    of    practically    pure    monochlor- 
acetic    acid,    which    quickly    solidifies    on    cooling.     The 
colorless,    crystalline   plates   are   separated   at   the   filter 
pump  and  redistilled.     The  portion  passing  over  between 
i85°-i9o°  C.  is  collected. 

55.  Acetamide  (CH3CONH2).     Half  fill  a  number  of 
heavy-walled    pressure    tubes    with    ammonium    acetate. 
After  properly  sealing,  place  in  a  bomb  furnace  and  heat 
for  five  hours  at  a  temperature  of  230°  C.     During  the 
heating,  care  should  be  taken  not  to  open  the  furnace  or 
even  look  in  at  the  tubes.     After  heating  the  tubes  for 
five  hours,  the  furnace  is  allowed  to  cool,  and  the  tubes 


ORGANIC  PREPARATIONS 


37 


removed,  carefully  opened,  and  distilled,  using  an  air 
condenser.  That  portion  passing  over  at  above  180°  C. 
is  nearly  pure  acetamide,  which  on  cooling  gives  almost 
colorless  rhombohedral  crystals. 

56.  Ethylene  Bromide  (C2H4Br2).  A  mixture  of  50 
gms.  of  absolute  alcohol  and  300  gins,  of  concentrated  sul- 
phuric acid  is  heated  in  a  2 -liter  round-bottom  flask  on 
a  sand-bath  until  a  steady  stream  of  ethylene  is  evolved. 
A  mixture  of  i  part  of  alcohol  with  2  parts  of  sulphuric 


FIG.  19. 

acid  is  then  run  into  the  flask  through  a  tap  funnel  at  such 
a  rate  that  a  stream  of  ethylene  is  produced,  care  being 
taken  that  the  flask  does  not  froth  too  violently.  The 
gas  thus  generated  is  purified  by  passing  it  through  a 
series  of  wash  bottles  (Fig.  19),  the  first  of  which  is  empty; 
the  second  contains  concentrated  sulphuric  acid;  while 
the  third  and  fourth  are  provided  with  a  solution  of  caustic 
soda.  The  purified  gas  is  now  conducted  through  two 
Woulff  bottles  containing  bromine  covered  with  a  layer 
of  water.  The  last  bottle  in  the  series  holds  broken 
glass  and  soda-lime.  As  soon  as  the  bromine  takes  on  a 


38      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

pale  yellow  color,  it  is  removed,  and  more  bromine  intro- 
duced. After  the  desired  quantity  of  crude  ethylene 
bromide  has  been  obtained,  the  evolution  of  ethylene 
is  interrupted  and  the  product  washed  with  water  con- 
taining caustic  soda,  then  with  water  alone,  and  finally 
dehydrated  over  calcium  chloride  and  distilled.  That 
portion  boiling  at  about  130°  C.  is  collected  as  pure  ethylene 
bromide. 

57.  Succinic  Acid  (COOHCH2CH2COOH).  Two  hun- 
dred gms.  of  ethylene  bromide  and  150  gms.  of  potassium 
cyanide  in  alcoholic  solution  are  heated  on  a  water-bath 
in  a  2-liter  flask  connected  with  a  reflux  condenser.  The 
heating  is  continued  for  several  hours,  or  until  all  of  the 
potassium  cyanide  is  converted  into  bromide,  which 
separates  out  from  the  alcoholic  solution.  The  crystals 
of  potassium  bromide  are  then  filtered  off.  To  the  filtrate 
is  added  about  150  gms.  of  caustic  soda  and  the  mixture 
again  heated  on  the  water-bath,  with  reflux  condenser 
attached,  until  the  evolution  of  ammonia  ceases.  The 
contents  of  the  flask,  on  cooling,  are  acidified  with  dilute 
hydrochloric  acid  and  evaporated  to  dryness  on  the  water- 
bath.  The  dry  powder  is  next  treated  with  absolute 
alcohol,  which  dissolves  the  succinic  acid  and  is  separated 
from  it  on  the  water-bath  by  distillation.  The  slightly 
colored  product  remaining  in  the  flask  is  recrystallized 
from  hot  water  to  which  a  small  amount  of  animal  char- 
coal has  been  added.  As  the  filtrate  cools,  colorless, 
prismatic  crystals  separate. 

68.  Monobrombenzene  (CeHsBr).  Two  hundred 
gms.  of  benzene  and  105  gms.  of  bromine  are  mixed  to- 
gether in  a  round-bottom  flask  provided  with  reflux  con- 
denser (Fig.  20),  further  provision  being  made  to  absorb 


ORGANIC  PREPARATIONS 


39 


FIG.  20. 


the  escaping  gases  in  a  tower  containing  soda-lime.  The 
mixture  is  gently  heated  over  a  wire  gauze  until  the 
reaction  is  complete.  The 
contents  of  the  flask  are  aspi- 
rated with  dry  air  to  drive  off 
the  remaining  hydrobromic 
acid,  and  the  unattacked  ben- 
zene distilled  off  on  a  water- 
bath.  The  residue  from  the 
benzene  is  now  washed  in  a 
separatory  funnel  with  water 
containing  a  small  amount  of 
caustic  soda.  The  heavy  liquid 
is  carefully  removed  from  the 
separatory  funnel,  dehydrated 
over  fused  calcium  chloride,  and  distilled.  That  portion 
passing  over  between  150°-! 55°  C.  is  nearly  pure  mono- 
brombenzene. 

69.  Sodium  Benzene  Sulphonate  (C6H5S03Na).  A 
mixture  of  200  gms.  of  benzene  and  400  gms.  of  concentrated 
sulphuric  acid  is  heated  at  a  gentle  boil  for  twenty-four 
hours  in  a  i -liter  round-bottom  flask,  connected  with  a 
reflux  condenser.  At  the  end  of  this  time,  about  four- 
fifths  of  the  benzene  should  have  disappeared,  and  the 
lower  portion  should  assume  a  deep  black  color.  The 
unattacked  benzene  is  removed  by  means  of  a  separatory 
funnel,  and  the  residue  thrown  into  2  liters  of  water. 
The  liquid  is  then  neutralized  with  milk  of  lime,  and  the 
precipitate,  calcium  sulphate,  removed  by  means  of  a 
bag  filter.  The  solution  of  calcium  benzene  sulphonate  is 
concentrated  to  a  small  volume,  when,  on  cooling,  almost 
a  solid  mass  of  crystals  is  obtained.  The  salt  is  separated 


40      LABORATORY  GUIDE  OF  INDUSTRIAL   CHEMISTRY 

from  the  mother  liquor,  dissolved  in  hot  water,  and  exactly 
neutralized  with  a  concentrated  solution  of  sodium  car- 
bonate. The  solution  of  sodium  benzene  sulphonate  thus 
resulting  is  filtered  from  the  calcium  carbonate  and  con- 
centrated until  crystallization  is-  noticed.  The  crystals 
are  separated  and  dried  on  porous  plates,  the  mother  liquor 
being  concentrated  for  further  yield. 

60.  Phenol  (C6H5OH).     One  hundred  and  fifty  gms. 
of  caustic  soda  is  dissolved  in  the  smallest  possible  quan- 
tity of  water  and  heated  in  an  iron  crucible  on  a  sand- 
bath.     The  temperature  is  raised  to  about  300°  C.  and 
100  gms.   of   sodium   benzene   sulphonate   slowly   added, 
the  mixture  being  constantly  stirred.     The  mass  at  first 
becomes  thick,  then  finally  semi-fluid.     The  end  of  the 
reaction  is  indicated  when  the  color  becomes  somewhat 
lighter.     The  contents  are  then  cooled,  dissolved  in  water, 
and  neutralized  with  dilute  hydrochloric  acid.     The  phenol 
separates  as  a  light  yellow  oil  and  is  removed  by  means 
of  a  separatory  funnel.     On  distillation,  the  product  pass- 
ing over  between  i75°-i85°  is  nearly  pure  phenol. 

61.  Para  Cresol  (C6H4^  !?3).     Dissolve  50  gms.  of 


concentrated  sulphuric  acid  in  1500  cc.  of  water  and  add 
to  this  50  gms.  of  paratoluidine.  Cool  the  solution  to 
room  temperature  and  slowly  add  40  gms.  of  sodium 
nitrite  dissolved  in  100  cc.  of  water.  The  clear  solution 
is  gently  heated  on  the  water-bath  until  the  evolution  of 
nitrogen  ceases.  The  dark-colored  solution  is  now  steam- 
distilled  until  a  slight  cloudiness  appears,  when  bromine 
water  is  added  to  a  portion  of  the  distillate.  The  entire 
distillate  is  then  extracted  several  times  with  small  quan- 
tities of  ether,  and  the  ethereal  solution  dehydrated  over 


ORGANIC  PREPARATIONS 


41 


plaster  of  Paris.  After  filtering  off  the  precipitate,  the 
solution  is  heated  on  a  water-bath  to  remove  the  ether, 
and  the  remaining  liquid  distilled  over  a  naked  flame, 
using  an  air  condenser.  The  portion  passing  over  be- 
tween i95°-2oo°  C.  is  practically  pure  para  cresol. 

62.  Benzyl  Chloride  (C6H5CH2C1).  Boil  gently  200 
gms.  of  toluene  in  a  weighed  J-liter  retort,  provided  with 
reflux  condenser  (Fig.  21).  Into  the  boiling  liquid  conduct 
a  stream  of  chlorine,  preferably  in  direct  sunlight,  until  the 


0 


FIG.  21. 

retort  has  gained  75  gms.  in  weight.  When  the  reaction 
is  complete  distill  the  contents  of  the  retort  and  collect 
separately  the  fraction  passing  over  between  i65°-i85°  C. 
On  redistilling  this  product,  only  that  portion  between 
i76°-i8o°  C.  is  collected  as  nearly  pure  benzyl  chloride. 

63.  Benzaldehyde  (C6H5COH).  A  mixture  of  50  gms. 
of  benzyl  chloride,  40  gms.  of  copper  nitrate,  and  500  gms. 
of  water  is  heated  to  boiling  for  a  day  (eight  or  nine 
hours)  on  the  sand-bath,  in  a  round-bottom  flask  with 
upright  condenser.  A  slow  current  of  carbon  dioxide  is 


42      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

at  the  same  time  passed  through  the  liquid  to  prevent 
oxidation  of  the  benzaldehyde  by  absorption  of  oxygen 
from  the  air.  During  the  process  nitrous  fumes  are  slowly 
evolved.  When  the  reaction  is  complete,  the  contents 
of  the  flask  are  extracted  with  ether,  and  the  yellow  oil 
remaining  after  distilling  off  the  ether  is  shaken  with 
a  saturated  solution  of  sodium  bisulphite  and  allowed  to 
stand  for  some  time.  The  colorless,  crystalline  mass  which 
separates  out  is  filtered,  washed  with  a  little  alcohol  and 
ether,  and  then  drained  in  a  porcelain  filter.  The  alde- 
hyde is  regained  by  adding  dilute  sulphuric  acid  in  excess 
and  distilling  with  steam.  The  distillate  is  extracted 
with  ether,  dehydrated  over  calcium  chloride,  decanted, 
and  the  ether  distilled  off. 

64.  Anisol   (C6H5OCH3).     Pour   100  gms.   of  methyl 
alcohol   into    a   round-bottom   flask   connected   with   an 
upright  condenser.     Then  add  5  gms.  of  sodium  cut  into 
small  pieces.  '  When  the  sodium  has  dissolved,   add   20 
gms.  of  phenol  and  40  gms.  of  methyl  iodide.     The  mixture 
is  heated  on  the  water-bath  until  the  solution  no  longer 
has  an  alkaline  reaction  (two  to  four  hours).    As  much 
as  possible  of  the  methyl  alcohol  is  distilled  off  on  the 
water-bath  and  water  added  to  the  amber-colored  residue. 
The  colorless  oil  which '  separates  is  extracted  with  ether. 
The  ethereal  solution  is  dehydrated  over  calcium  chloride 
and  distilled,  first  on  the  water-bath,  until  the  ether  has 
been  driven  off,  and  then  over  the  flame.    Almost  all  of 
the  residue  distills  at  150°-!  5 5°. 

65.  Benzoic    Acid    (C6H5COOH).     Mix    50    gms.    of 
benzyl  chloride  with  40  gms.  of  soda  ash,  dissolved  in 
500  cc.  of  water,  and  heat  to  boiling  in  a  round-bottom 
flask  provided  with  a  reflux  condenser.     A  solution  of  85 


ORGANIC  PREPARATIONS  43 

gms.  of  potassium  permanganate  in  1000  cc.  of  water 
is  gradually  poured  in  through  the  top  of  the  condenser. 
After  boiling  for  about  three  hours,  the  pink  color  of  the 
permanganate  will  have  disappeared  and  a  heavy  pre- 
cipitate of  manganese  dioxide  formed.  The  solution  is 
then  filtered  and  the  filtrate  acidified  with  hydrochloric 
acid  and  allowed  to  cool;  whereupon  crystals  of  benzoic 
acid  separate. 

66.  Methyl  Benzoate  or  Niobe  Oil   (C6H5COOCH3). 
Dissolve  50  gms.  of  benzoic  acid  in  an  excess  of  methyl 
alcohol    and    saturate   with    dry    hydrochloric    acid   gas. 
After  saturation  the  solution  is  heated  for  about  four 
hours  on  a  steam-bath  and  then  poured  into  an  equal 
volume  of  water.    The  oil  which  separates  is  purified  by 
rectification. 

67.  Benzoyl  Chloride  (C6H5COC1).    Treat  50  gms.  of 
benzoic  acid  in  a  dry  5oo-cc.  flask  with  90  gms.  of  finely 
pulverized    phosphorus    pentachloride,    under    the    hood. 
The  two  are  shaken  well  together,  whereupon  an  energetic 
action  takes  place  with  the  evolution  of  hydrochloric  acid; 
in  order  to  prevent  the  cracking  of  the  flask,  place  it  on 
a  wooden  block  and  not  on  any  stone  or  porcelain.    After 
standing  for  a  time,  it  is  twice  fractionated,  using  a  long, 
wide  air  condenser. 

68.  Nitrobenzene  (C6H5N02).     Two  hundred  and  forty 
gms.  of  nitric  acid,  sp.  gr.  1.4,  is  added,  a  small  portion  at 
a  time,  to  360  gms.  of  sulphuric  acid,  sp.  gr.  1.82,  in  a 
looo-cc.  flask.    During  tins  operation  the  flask  is  well  cooled 
under  the  tap.     The  mixture  is  transferred  to  a  tap  funnel 
and  added  slowly  to  200  gms.  of  benzol  in  a  2-liter  flask. 
The  flask  is  well  shaken  after  each  addition,  and  the  tem- 
perature not  allowed  to  rise  above  25°  C.  until  nearly 


44      LABORATORY   GUIDE  OF  INDUSTRIAL  CHEMISTRY 

all  of  the  acid  has  been  added.  A  wide  glass  tube  is 
now  attached  by  a  cork  to  the  flask,  forming  an  air  con- 
denser, and  the  mixture  heated  on  the  water-bath  for 
an  hour  at  60°  C.,  being  frequently  shaken.  The  contents 
of  the  flask  are  poured  into  about  2  liters  of  water,  when 
the  nitrobenzene  settles  to  the  bottom  and  can  be  removed 
by  means  of  a  separatory  funnel.  It  is  then  washed  several 
times  with  water.  The  nitrobenzene  is  next  run  into  a 
distilling  flask  fitted  with  a  thermometer  and  connected 


FIG.  22. 

with  a  long  glass  tube  about  8-10  mm.  in  diameter,  forming 
an  air  condenser  (Fig.  22).  The  oil  is  distilled  over  a 
free  flame.  At  first,  water  and  benzene  pass  over,  then 
the  temperature  rises  rapidly  to  over  200°  C.,  when  the 
receiver  is  changed  and  the  nitrobenzene  collected  at  204°- 
207°  C. 

69.  Metadinitrobenzene  (C6H4(N02)2).  To  a  mixture 
of  70  gms.  of  fuming  nitric  acid  and  70  gms.  of  sulphuric 
acid  add  100  gms.  of  nitrobenzene,  shaking  the  flask  well 
after  each  addition  and  maintaining  the  temperature  at 
about  75°  C.  When  all  of  the  nitrobenzene  has  been  added, 


ORGANIC  PREPARATIONS  45 

heat  the  flask  for  a  short  time  on  the  water-bath  until 
a  test  portion,  when  thrown  into  water,  forms  a  yellow 
solid.  While  the  entire  reaction  product  is  still  warm, 
throw  into  a  large  quantity  of  water.  The  metadinitro- 
benzene,  mixed  with  a  small  amount  of  ortho  and  para 
compounds/  separates,  on  standing,  as  a  yellow  crys- 
talline mass,  which  is  filtered  at  the  pump  and  washed 
with  cold  water.  The  mixed  compounds  are  dissolved 
in  hot  dilute  alcohol,  from  which,  on  cooling,  the  pure 
metadinitrobenzene  crystallizes  in  light  yellow  needles. 

70.  Ortho-  and  Para-Nitrophenol  fc$Ht™    .     One 


hundred  gms.  of  phenol  is  melted  and  slowly  added  to 
a  mixture  of  175  gms.  of  nitric  acid  in  400  cc.  of  water 
and  well  shaken  after  each  addition.  When  all  of  the 
phenol  has  been  added,  the  mixture  is  allowed  to  stand 
overnight.  The  heavy,  oily  layer  in  the  bottom  of  the 
flask  is  washed  several  times  by  decantation.  The  mixture 
of  the  ortho  and  para  compounds  is  then  subjected  to 
steam  distillation,  when  the  ortho  compound  passes  over 
as  a  yellow  liquid  that  becomes  solid  upon  cooling  and 
is  separated  at  the  pump. 

The  residue  in  the  flask  consists  of  the  para  compound 
mixed  with  resinous  matter  from  which  it  is  separated 
by  repeatedly  extracting  with  boiling  water.  To  purify 
the  product,  make  it  alkaline  with  caustic  soda  and  boil 
again.  Filter  and  concentrate  the  filtrate  until  crystals 
of  the  sodium  salt  separate.  The  latter  are  dissolved  in 
hot  water,  neutralized  with  hydrochloric  acid,  separated 
by  filtration,  and  recrystallized  from  hot  water. 

71.  Picric  Acid  (C6H2(NO2)30H).  Heat  together  on 
a  water-bath  to  about  100°  C.  a  mixture  of  20  gms.  of 


46      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

phenol  and  20  gms.  cone,  sulphuric  acid  until  complete 
solution  takes  place.  Dilute  with  twice  the  volume  of 
water  and  transfer  to  a  separatory  funnel.  Now  add  this 
mixture  gradually,  carefully,  and  with  constant  shaking, 
to  100  gms.  of  cone,  nitric  acid.  Warm  the  mixture  on 
a  water-bath  until  the  red  color  changes  to  yellow,  then 
pour  into  a  liter  of  water,  filter  off  the  crystals,  drain 
thoroughly,  wash  with  water,  and  recrystallize  from  hot 
water  containing  10  per  cent  sulphuric  acid. 

Dye  a  skein  of  worsted  and  silk  in  a  solution  of  the 
acid  as  given  in  dye- test  Nos.  124  and  129.  Be  careful 
with  the  salts  of  this  acid,  as  they  explode  when  heated 
or  struck. 

72.  Cinnamic  Acid  (C6H5CH:CHCOOH).    A  mixture 
of  20  gms.  benzaldehyde,  30  gms.  acetic  anyhdride,  and 
10  gms.  anhydrous  pulverized  sodium  acetate  is  heated 
in  a  flask  provided  with  a  wide  vertical  air  condenser  for 
eight  hours  in  an  oil-bath  at  180°  C.     If  the  experiment 
cannot  be  made  at  one  time,  a  calcium  chloride  tube  may 
be  placed  over  the  end  of  the  condenser.    After  the  reac- 
tion is  complete,  pour  the  hot  reaction  product  into  a 
large  flask,  add  water,  and  distill  with  steam  (see  Fig.  23), 
until  no  more  benzaldehyde  passes  over.    The  quantity 
of  water  used  here  is  large  enough  to  dissolve  all  the 
cinnamic  acid  except  a  small  oily  impurity.     The  solution 
is  then  boiled  a  short  time  with  some  animal  charcoal 
and   filtered.     On   cooling,   the    cinnamic    acid    separates 
out    in    lustrous    leaves.     Drain    and    dry.      Determine 
melting-point. 

73.  Salicylic  Acid  (C6H4\roOH/      -Di550^  I0°  Sms- 
of  caustic  soda  in  100  cc.  of  water  in  an  iron  crucible  and 


ORGANIC   PREPARATIONS  47 

add  230  gms.  of  phenol.  Heat  the  retort  gently  and  stir 
well  with  a  small  iron  rod.  As  soon  as  the  mass  becomes 
stiff,  the  flame  should  be  removed  and  the  stirring  continued 
until  the  lumps  are  broken  up.  The  mass,  while  yet 
warm,  is  powdered  in  a  mortar,  transferred  to  a  retort, 
and  heated  in  an  oil-bath  to  a  temperature  of  about  130° 
C.,  the  apparatus  being  aspirated  by  means  of  dry  air 
until  moisture  is  removed.  The  mass  is  then  again  trans- 
ferred to  the  mortar,  quickly  powdered,  and  returned  to 
the  retort.  A  stream  of  dry  carbon  dioxide  is  now  passed 
over  the  surface  of  the  dry  mixture  and  the  temperature 
of  the  oil-bath  raised  to  190°  C.  After  heating  for  four 
hours,  the  temperature  is  again  raised  to  200°,  the  heating 
continued  for  another  hour  and  then  stopped.  The  mass 
is  now  shaken  out  into  a  suitable  vessel  and  sufficient  water 
added  to  dissolve  it.  The  solution  is  next  made  acid  with 
hydrochloric  acid,  allowed  to  cool,  and  filtered.  The  dark- 
colored  precipitate  of  impure  salicylic  acid  is  washed 
from  the  filter,  boiled  with  water  containing  a  small 
amount  of  animal  charcoal,  filtered  again,  and  the  filtrate 
allowed  to  cool,  when  needle-shaped  crystals  of  salicylic 
acid  separate. 

74.  Aniline  (C6H5NH2).  Place  240  gms.  of  iron 
powder  with  320  cc.  of  water  in  a  large  flask  (2-3  liters) 
and  shake  well.  Warm  the  flask  slightly  and  add  a  few 
drops  of  nitrobenzene.  Then  pour  20  gms.  of  hydro- 
chloric acid  into  the  flask  and  introduce  the  remainder 
of  the  nitrobenzene  (200  gms.  in  all).  Add  the  latter 
in  small  portions  and  after  each  addition  shake  the  flask 
thoroughly  and  cool  under  the  tap.  The  addition  of  the 
nitrobenzene  is  so  regulated  as  to  keep  the  temperature  at 
about  8o°-9O°  C.  When  no  further  rise  in  temperature 


48      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 


on  shaking  indicates  that  the  reaction  is  finished,  neu- 
tralize excess  of  acid  with  hydrated  lime  and  distill  the 
contents  of  the  flask  with  steam  (Fig.  23)  until  the  distillate 
is  no  longer  milky,  then  transfer  it  to  a  separatory  funnel 
and  draw  off  the  aniline.  The  water  is  now  saturated 


FIG.  23. 

with  salt,  and  the  oil  which  rises  to  the  top  is  added  to 
the  first  portion,  and  the  whole  distilled.  A  little  water 
passes  over  at  first  and  is  collected  separately;  then 
aniline  passes  over  at  182°. 

75.  Dimethyl  Aniline  (C6H5N(CH3)2).    A  mixture  of 
150  gms.  of  aniline,  50  gms.  of  aniline  hydrochloride,  and 
150  gms.  of  methyl  alcohol  is  heated  in  an  iron  autoclave 
for  seven  or  eight  hours  at  2^-240°  C.     The  product 
is  then  made  alkaline  with  NaOH,  distilled  with  steam, 
and  the  oil  separated.     The   product  is  dried   over  solid 
caustic   potash,   and    the    fraction    boiling  at    i90°-2oo° 
collected. 

76.  ^-Sulphanilic  Acid  (c6H4<(:^!  \    Two  hundred 
gms.  of  aniline  is  stirred  into  220  gms.  of  cone,  sulphuric 


ORGANIC  PREPARATIONS  49 

acid  in  a  shallow  porcelain  dish,  and  the  acid  sulphate 
thus  obtained  (CeHsNHUH^SOJ  is  heated  in  an  oven 
until  the  temperature  reaches  205°  C.  This  must  take 
four  hours.  The  oven  is  kept  at  this  temperature  for 
six  hours  or  more.  The  product  is  broken  up  and  dis- 
solved in  hot  water  with  the  addition  of  80  gms.  of  caustic 
soda  (alkaline  reaction  must  be  obtained).  The  solution 
of  sodium  sulphanilate  is  boiled  for  a  few  minutes  with 
a  little  animal  charcoal  and  filtered  hot.  On  acidifying 
with  hydrochloric  acid  (Congo  paper  must  be  turned  blue), 
the  sulphanilic  acid  crystallizes  out.  After  standing  over- 
night it  is  filtered  at  the  pump  and  dried  at  100°  C. 

77.  Acetanilide  (C6H5NHC2H30).    Two  hundred  gms. 
of  aniline  and  150  gms.  of  glacial  acetic  acid  are  mixed  in 
a  round-bottom  flask  of  i  liter  capacity,  fitted  with  a  reflux 
air  condenser,  and  boiled  on  a  sand-bath  for  ten  or  twelve 
hours.     The  hot  liquid  is  poured  into  hot  water  con- 
taining 30  gms.  of  hydrochloric  acid,  and  the  whole  well 
stirred.     After  cooling,   the  acetanilid  is  filtered   at  the 
pump,  washed  with  cold  water,  recrystallized  from  hot 
water,  and  dried  in  the  centrifugal. 

78.  ^-Nitracetanmde(C6H4NH(CH3CO)N02).  Dissolve 
200  gms.  of  acetanilide  in  600  gms.  of  sulphuric  acid  in 
a  round-bottom  flask,  the  temperature  not  being  allowed 
to  rise  above  40°.     The  solution  is  cooled  to  5°-io°  by 
immersion  in  ice- water,  and  a  cool  mixture  of  125  gms. 
nitric  acid  and   100  gms.  of  sulphuric  acid  added  very 
slowly.     After   each   addition    the   flask   is   well   shaken 
and    cooled    in    ice- water,    the    temperature    being   kept 
below   15°.     After  standing  a  short  tune,   the  nitration 
mixture  is  poured  into  about  20  liters  of  water  containing 
several  pieces  of  ice,  when  the  />-nitracetanilide  separates. 


50      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

It  is  filtered,  washed  free  from  acid,  and  dried  on  a 
porous  plate. 

79.  ^-Nitraniline  (c6H4<^    2j.     Two  hundred  gms. 

of  ^-nitracetanilide  is  boiled  with  500  cc.  of  dilute  sulphuric 
acid  (25  per  cent)  in  a  round-bottom  flask,  connected 
with  a  reflux  condenser,  until  the  whole  dissolves.  The 
clear  solution  is  poured  into  a  beaker,  and  the  free  base 
precipitated  by  adding  dilute  caustic  soda  solution  until 
alkaline.  After  cooling,  the  ^-nitraniline  is  filtered,  re- 
crystallized  from  hot  water,  and  dried  on  a  porous  plate. 

80.  Benzidine  (NH2-  CeHr  C6HV NH2).     One  hundred 
gms.  of  caustic  soda  is  dissolved  in  300  cc.  of  water  in  a 
2-liter  flask  and  a  mixture  of  50  cc.  of  ethyl  alcohol  and 
100  gms.  of  nitrobenzene  added.     The  flask  is  then  con- 
nected  with   a   Liebig's   reflux   condenser.     Through  the 
top  of  the  condenser  add  170  gms.  of  zinc  dust  in  small 
portions,  shaking  well  and  allowing  any  foaming  to  subside 
before  introducing  a  fresh  quantity.      The  brown  color 
noticed  at  first  disappears  as  the  reduction  progresses, 
until  the  contents  appear  grayish  white,  usually  accom- 
plished by  heating  on  the  sand-bath  toward  the  end  of 
the  reaction.    The  contents  of  the  flask  on  cooling  are 
diluted  with  water;    ice  is  added;    and  then  the  whole 
is  acidified  with  hydrochloric  acid,  care  being  taken  that 
the  temperature  does  not  exceed  15°  C.     The  precipitate, 
consisting   of   hydrazo-benzene   and   undissolved   zinc,   is 
filtered   through   glass   wool.     It  is   then   removed   from 
the  funnel  and  boiled  with  500  cc.  of  water  to  which  strong 
hydrochloric   acid   is   added   as   long   as   absorbed.     The 
solution,  on  being  filtered,  is  treated  with  sulphuric  acid, 
which   precipitates   the   benzidine   as   sulphate.     This   is 


ORGANIC  PREPARATIONS  51 

filtered  off,  washed  with  cold  water,  and  then  boiled  with 
dilute  caustic  soda  solution.  The  pure  benzidine  now 
separates  and,  on  cooling,  crystallizes  in  large  silky  plates. 

81.  Naphthalene  0-Sulphonic  Acid  (Ci0H7HS03).    Two 
hundred  and  forty  gms.   of  concentrated  sulphuric  acid 
is  warmed  to  100°  C.  and  200  gms.  of  powdered  naphthalene 
gradually  added.     The  mixture  is  then  heated  at  170°  C. 
for  twelve  hours.     The  sulphonation  mixture,  on  cooling, 
is  poured  into  3  liters  of  water,  brought  to  a  boil,  and 
sufficient  milk  of  lime  added  to  produce  an  alkaline  reac- 
tion.    The  precipitate  of  calcium  sulphate  is  filtered  at 
the  suction  pump  and  washed  with  boiling  water.     The 
filtrate  and  washings  are  evaporated  to  a  small  volume 
and  allowed  to  stand  overnight,  when  the  calcium  salt 
of  naphthalene  /3-sulphonic  acid  separates.     The  calcium 
salt  is  now  dissolved  in  hot  water  and  sufficient  sodium 
carbonate  added  to  combine  with  all  of  the  calcium  as 
carbonates — care  should  be  taken  not  to  add  an  excess. 
The  precipitate  of  calcium  carbonate  is  filtered  off  and 
the  filtrate  evaporated  until  crystals  appear.     It  is  then 
set  aside  overnight  and,  the  crystals  being  separated,  the 
mother  liquor  is  evaporated  for  a  further  yield. 

82.  /3-Naphthol  (Ci0H7OH).     Six  hundred  gms.  of  caus- 
tic soda  and  60  gms.  of  water  are  placed  in  an  iron  crucible 
and  heated  to  280°  C.     Care  must  be  taken  to   inclose 
the  bulb  of  the  thermometer  in  copper  foil;    the  hands 
should  be  protected  with  thick  gloves,  and  the  eyes  with 
goggles.     To  the  heated  caustic  soda,  200  gms.  of  sodium 
naphthalene  0-sulphonic  acid  is   cautiously  added,   care 
being  taken   that  the  temperature  does  not  fall  below 
260°  C.     The  temperature  is  now  raised  to  320°  C.     When 
the  mass  froths  and  becomes  liquid,  the  reaction  is  com- 


52      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

plete.  The  liquid  is  now  thrown  on  shallow  iron  pans 
and,  when  cool,  is  broken  up  and  dissolved  in  hot  water. 
To  the  solution  of  sodium  /3-naphtholate,  concentrated 
hydrochloric  acid  is  added,  and  the  impure  0-naphthol  is 
filtered  at  the  pump.  To  further  purify  the  product,  it 
is  distilled  in  a  vacuum. 

83.  jS-Naphthol-6-Sulphonic    Acid     (Schaeffer's     Salt) 

f  Ci0H6<^  ).     Two    hundred  gms.  of  finely  divided 

/3-naphthol  is  gradually  added  to  400  gms.  of  sulphuric  acid 
previously  warmed  to  35°  C.  The  mixture  is  then  heated 
on  the  water-bath  to  100°  C.  for  eight  hours.  The  re- 
sulting product  is  dissolved  in  2  liters  of  water  and  satu- 
rated with  common  salt.  The  sodium  salt  of  the  naphthol 
sulphonic  acid  separates  on  standing  and  is  filtered  off, 
washed  with  saturated  salt  solution  until  free  from  acid, 
and  then  dried. 

84.  /3-Naphthol-3  :  6-Disulphonic     Acid     ("  R    Salt  ") 

( CioH5<\~o  --.v    ).     Eight   hundred    gms.    of    sulphuric 

acid  is  heated  to  125°  C.,  200  gms.  of  finely  powdered 
/3-naphthol  added,  and  the  temperature  kept  at  125°  C. 
for  six  hours.  The  reaction  product  is  now  thrown  into 
3  liters  of  water  and  neutralized  with  milk  of  lime.  The 
calcium  sulphate  is  filtered  off  and  the  precipitate  washed 
with  boiling  water.  To  the  filtrate  and  washing  is  added 
sodium  carbonate,  and  the  resulting  calcium  carbonate 
removed  on  the  suction  filter.  The  "  R  Salt "  is  pre- 
cipitated from  the  filtrate  by  the  addition  of  common 
salt,  the  mixture  being  allowed  to  stand  overnight. 

85.  tt-Nitronaphthalene  (Ci0H7NO2).    To  a  mixture  of 
400  gms.  of  nitric  acid  and  500  gms.  of  sulphuric  acid 


ORGANIC  PREPARATIONS  53 

slowly  add  500  gms.  of  finely  powdered  naphthalene. 
Shake  the  flask  well  and  cool  it  after  each  addition,  keeping 
the  temperature  at  about  50°  C.  After  adding  all  of  the 
naphthalene  heat  the  mixture  for  two  hours  at  60°  C. 
and  pour  into  cold  water.  The  solid  cake  which  settles 
to  the  bottom  is  washed  several  times  with  cold  water, 
then  with  boiling  water.  The  melted  product  is  now 
subjected  to  steam  distillation  to  remove  excess  of  naph- 
thalene. The  residue  in  the  flask  is  poured  into  cold 
water  when  the  nitronaphthalene  separates  out  as  a  gran- 
ular solid. 

86.  a-Naphthylamine  (Ci0H7NH2).     One  hundred  and 
sixty  gms.  of  iron  filings  are  mixed  with  80  cc.  of  water 
and  warmed  to  about  50°  C.     To  this  is  added  25  cc.  of 
concentrated   hydrochloric   acid,   and   then    120  gms.    of 
a-nitronaphthalene  is  slowly  introduced,  temperature  being 
maintained  at  about  70°  throughout  the  reduction.     When 
the  reaction  is  complete — indicated  by  no  further  rise  in 
temperature — a  small  amount  of  milk  of  lime  is  added 
until  an  alkaline  reaction  is  obtained,  and  the  mass  allowed 
to  cool.     The  precipitate,  which  is  separated  at  the  pump, 
is  dried  in  the  air  and  distilled  under  reduced  pressure. 

87.  Anthraquinone    (CeH^CO^CeHO.     Twenty   gms. 
of  anthracene  is  dissolved  in  240  gms.  glacial  acetic  acid 
by  boiling  them  together  in  a  round-bottom  flask  (i -liter) 
with  upright  condenser  over  wire  gauze.    A  solution  of 
40  gms.  of  chromium  trioxide  in  30  cc.  of  water  and  150 
cc.  of  glacial  acetic  acid  is  then  dropped  in  from  a  tap 
funnel  pushed  into  the  top  end  of  the  condenser,  while 
the  liquid  is  kept  cooling.     This  operation  should  consune 
about  one  hour.     The   solution  becomes  a  deep  green. 
It  is  allowed  to  cool  and  is  poured  into  water  (i  liter) 


54      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

which  precipitates  the  anthraquinone  in  the  form  of  a 
brown  powder.  After  standing  for  one  hour  it  is  filtered 
through  a  large  folded  filter,  washed  with  a  little  hot 
water,  then  with  warm  dilute  caustic  soda,  and  again 
with  water.  It  may  be  purified  by  sublimation. 

88.  Anthraquinone  Sulphonic  Acid   (CeH^CO^CeHa- 
HS03).     Add  100  gins,  finely  powdered  anthraquinone  to 
100  gms.  of  sulphuric  acid  and  heat  the  mixture  gradually 
in  an  oil-bath  until  a  temperature  of   160°  is  obtained. 
The  mixture  is  slowly  and  carefully  poured  into  hot  water 
(2   liters),    the   solution   boiled   for   some   time,   and   the 
unchanged  anthraquinone  filtered  off  at  the  pump.     The 
filtrate  is  neutralized  with  caustic  soda  and  allowed  to 
cool,  when  the  greater  part  of  the  sodium  anthraquinone 
sulphonate  crystallizes  out.     This  is  the  so-called  "  silver 
salt."     A  second  crop  of  crystals  may  be  obtained  by  fur- 
ther concentration  of  the  filtrate,  but  is  apt  to  be  con- 
taminated with  sodium  sulphate. 

89.  Fluorescein  (C2oHi2O5).     Grind  together  and  heat 
in  an  oil-bath  to  180°  C.  30  gms.  phthalic  anhydride  and 
44  gms.  resorcinol.     For  this  purpose  a  nickel  dish  may  be 
used.    As  soon  as  the  temperature  has  reached  180°  C., 
14  gms.  of  zinc  chloride  is  added  gradually    during    ten 
minutes,  the  melt  being  stirred  with  a  glass  rod.    After 
the  zinc  chloride  has  been  added  the  temperature  is  raised 
to  210°  C.  and  maintained  until  the  mass  becomes  solid 
(one  to  two  hours).     The  cold  melt  is  broken  out  of  the 
crucible  with  a  chisel  or  knife,  powdered,  and  dissolved 
in  dilute  caustic  soda.     After  filtering,  hydrochloric  acid 
is  added,  which  precipitates  the  fluorescein;  this  is  filtered, 
washed    and    dried. 

90.  Eosine  (C2oH6Br405Na2).     Place  15  gms.  of  fluor- 


ORGANIC  PREPARATIONS  55 

escein  in  a  flask,  add  60  gms.  of  alcohol,  and  drop  in 
slowly  from  a  small  separatory  funnel  33  gms.  of  bromine. 
When  half  the  bromine  has  been  added,  the  dibromide 
formed  is  in  solution;  but  on  further  addition  of  bromine 
the  tetrabromide  separates  out.  After  standing  for  two 
hours  the  precipitate  is  filtered,  washed  with  water,  and 
converted  into  the  sodium  salt  by  mixing  it  with  a 
little  hot  water,  carefully  neutralizing  with  caustic  soda 
(avoiding  an  excess  of  this  reagent)  and  then  evaporating 
to  dryness  on  the  water-bath. 

91.  Fast  Green  O  (Dinitrosoresorcine). 

O 


NOH 


NOH 


Forty  gms.  resorcinol  is  dissolved  in  1600  cc.  of  water 
and  90  gms.  cone,  hydrochloric  acid  added,  together  with 
200  gms.  of  common  salt.  Ice  is  added  till  the  tempera- 
ture is  4°  C.,  and  into  this  solution,  which  is  stirred 
mechanically,  51  gms.  of  sodium  nitrite,  dissolved  in  200 
cc.  of  water,  is  allowed  to  flow  very  slowly,  the  tem- 
perature not  being  allowed  to  rise  above  8°.  This  takes 
about  half  an  hour.  When  all  of  the  nitrite  has  been 
added,  the  liquid  should  show  a  faint  acid  reaction.  After 
standing  for  one  hour,  the  brownish-yellow  precipitate  is 
filtered,  washed  with  ice-cold  water,  and  the  paste  dried 
on  a  porous  plate. 

92.  Naphthol  Yellow  S  (CioH^NC^SC^Ka).    Warm 
400  gms.  concentrated  sulphuric  acid  in  a  round-bottom 


56      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

flask  to  100°  C.,  and  then  add  gradually  100  gms.  finely 
powdered  a-naphthol.  Now  raise  the  temperature  to 
120°  and  keep  at  this  point  for  three  or  four  hours.  Pour 
the  sulphonation  mixture  into  600  cc.  of  water  and  stir 
mechanically.  As  soon  as  the  temperature  is  about  30°, 
add  200  gms.  of  cone,  nitric  acid  very  slowly,  drop  by  drop, 
through  a  tap  funnel  and  do  not  allow  the  temperature 
to  exceed  45°.  The  dinitronaphthol  sulphonic  acid  which 
separates  out  after  standing  is  filtered  at  the  pump,  washed 
with  saturated  salt  solution  until  free  from  acid,  and 
mixed  with  boiling  water.  Potassium  carbonate  is  now 
added  until  an  alkaline  reaction  is  obtained,  and,  after 
cooling,  the  precipitated  potassium  salt  is  filtered  and 
dried  on  a  porous  plate. 
93.  Orange  II. 

OH 


S03Na<  >N  :  N 


34.6  gms.  of  ^-sulphanilic  acid  is  dissolved  in  water  by 
careful  addition  of  caustic  soda  solution.  Ice  is  added 
until  the  temperature  is  5°  C.,  the  volume  of  the  whole 
being  about  i  liter;  §0  cc.  of  cone,  hydrochloric  acid  is 
poured  in,  and  then  slowly  14.48  gms.  of  sodium  nitrite, 
dissolved  in  a  small  quantity  of  water  added.  Tests  are 
made  from  time  to  time  with  starch  iodide  paper,  and  a 
slightly  blue  coloration  should  be  obtained  when  all  of 
the  nitrite  has  been  added.  The  diazo-compound  sep- 
arates out  in  fine  white  needles.  Twenty-eight  and  eight- 
tenths  gms.  of  /3-naphthol  is  dissolved  by  heating  it  with 


ORGANIC  PREPARATIONS  57 

a  solution  of  9  gms.  of  caustic  soda  in  30  cc.  of  water, 
and  the  sodium  naphtholate  solution  thus  formed  is 
poured  into  320  cc.  of  cold  water  and  cooled  if  necessary 
to  about  15°.  This  solution  is  stirred  and  the  diazo- 
compound  (in  suspension)  run  in  gradually.  When  the 
whole  of  the  diazo-compound  has  been  added,  the  mass 
should  show  a  weak  alkaline  reaction.  The  mass  is 
stirred  for  an  hour  longer,  when  nearly  all  of  the  coloring- 
matter  will  have  separated.  A  little  salt  solution  is  added 
to  aid  in  the  precipitation,  until  a  test  on  filter  paper 
shows  only  a  pink  orange  rim. 

Dye  a  skein  of  worsted  and  silk  as  under  tests  Nos. 
124  and  127. 

94.  Alizarine     (c6H4(CO)2C6H2<(^V      Three    hun- 
dred gms.  of  caustic  soda  is  dissolved  in  300  cc.  of  water 
in  an  autoclave  and  100  gms.  of  sodium  anthraquinone 
sulphonate  stirred  in.     Eighteen  gms.  of  potassium  chlor- 
ate is  dissolved  in  100  cc.  of  water  (hot)  and  thoroughly 
mixed  with  the  mass.     The  lid  of  the  autoclave  is  then 
fixed  on  and  the  whole  heated  for  20  hours  170°.     After 
cooling,  the  melt  is  extracted  with  boiling  water  several 
times,  and  the  solution  acidified  with  hydrochloric  acid. 
The  alizarine   which   separates  is  filtered  at  the  pump, 
washed  with  water,  pressed  on  a  porous  plate,  and  dried 
at  120°  C. 

95.  Methylene  Blue. 

N 


(CH,).      

>N(CH3)C1 


58      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

Twenty-four  gms.  of  dimethyl  aniline  is  dissolved  in  a 
mixture  of  80  cc.  of  water  and  130  gms.  of  concentrated 
hydrochloric  acid,  and  the  solution  cooled  with  ice  to 
i2°-i5°.  This  is  stirred  mechanically,  and  a  solution 
of  14.2  gms.  of  sodium  nitrite  run  in  slowly  (delivery  tube 
underneath  the  surface  of  the  liquid),  care  being  taken  that 
the  temperature  does  not  rise  above  15°.  The  nitroso 
compound  is  reduced  by  carefully  adding  about  40  gms. 
of  zinc  dust.  The  reduction  is  complete  when  the 
solution  is  of  a  clear  red  color.  The  amount  of  zinc  added 
must  be  sufficient  to  neutralize  the  hydrochloric  acid 
(so  that  Congo  paper  is  no  longer  turned  blue).  The 
solution  is  now  diluted  with  water  to  1000  cc.  and  a  solu- 
tion of  24  gms.  of  dimethyl  aniline  in  the  exact  quantity 
of  hydrochloric  acid  necessary  to  form  the  hydrochloride 
(about  20  cc.)  added,  and  then  a  solution  of  100  gms. 
of  sodium  thiosulphate  in  a  little  water  introduced. 

The  mixture  is  oxidized  by  adding  a  concentrated  solu- 
tion of  50  gms.  of  potassium  dichromate  and  boiling  for 
two  hours;  106  gms.  of  sulphuric  acid  diluted  with  200 
cc.  of  water  is  now  added  and  the  solution  boiled  to 
expel  SO  2. 

The  leuco-methylene  blue  is  oxidized  by  adding  16 
gms.  of  neutral  sodium  chromate  dissolved  in  a  little 
water,  and  the.  resulting  dye  precipitated  by  adding 
salt.  The  base  is  filtered,  dissolved  in  a  little  boiling 
water,  to  which  a  little  hydrochloric  acid  has  been  added, 
and  the  hydrochloride  precipitated  by  common  salt, 
filtered,  and  dried  on  a  porous  plate. 

96.  Indulin.  (a)  Spirit  Soluble.  Weigh  off  1000  gms. 
of  aniline  in  a  small  stoneware  pitcher  or  a  beaker  and 
add  96  gms.  22°  Be.  hydrochloric  acid,  stirring  vigorously. 


ORGANIC  PREPARATIONS  59 

Now  add  slowly  and  with  constant  stirring  a  solution 
of  57.6  gms.  sodium  nitrite  in  120  cc.  of  water.  Allow 
the  mixture  to  stand  overnight  and  then  warm  to  40° 
C.  for  one  hour  to  convert  the  diazoamidobenzene  at  first 
formed  into  aminoazobenzene.  The  warming  is  done  by 
placing  the  pitcher  or  beaker  in  warm  water.  Next, 
transfer  the  mixture  to  an  enameled  pot  with  a  cover 
(about  i  gal.  capacity),  or,  preferably,  a  small  enameled 
still  of  the  same  size  provided  with  a  detachable  cover 
(Fig.  24)  and  an  opening  for  a  ther- 
mometer. Now  add  240  gms.  of  aniline 
hydrochloride.  Heat  the  container  grad- 
ually, raising  the  temperature  to  175°  C. 
This  takes  from  one  to  one  and  one-half 
hours,  but  the  heating  is  continued  for  five 
hours,  keeping  the  temperature  as  close  to 
183°  C.  as  possible.  The  precaution  must 
be  observed  in  heating  to  have  a  sheet  of 
asbestos  under  the  pot  large  enough  to  project  some 
distance  beyond  the  rim,  otherwise  the  escaping  fumes  will 
reach  the  flame  and  ignite  the  batch.  In  using  the  still 
this  danger  is  avoided,  because  the  vapors  are  condensed. 
When  the  aniline  in  the  condensation  is  later  recovered 
by  salting  out. 

When  the  heating  is  complete,  the  melt  is  cooled  suffi- 
ciently and  then  steam -distilled  to  remove  excess  aniline. 
The  melt  is  poured  into  a  distilling  apparatus;  a  3-gal. 
chlorinating  pot  (Fig.  25)  serves  this  purpose  very  well. 
The  pot  is  provided  with  a  live,  steam  inlet  at  one  opening 
and  a  condenser  at  the  other.  One  thousand  cc.  of  water  is 
added  and  the  mass  steam-distilled  rapidly  until  the  distil- 
late is  clear  and  free  from  aniline  oil  globules.  The  spirit- 


60      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

soluble  indulin  (about  240  gms.)  is  left  as  a  sticky  mass 
at  the  bottom  of  the  vessel.  On  cooling,  it  becomes 
hard  and  brittle,  and  is  easily  ground  to  a  fine  powder. 
From  the  distillate  the  aniline  is  recovered  by  adding 
enough  salt  to  give  a  specific  gravity  of  about  1.026, 
whereupon  the  aniline  rises  to  the  top  and  is  drawn  off. 
(b)  Water  Soluble.  Eight  hundred  gms.  of  concentrated 
sulphuric  acid  is  heated  in  a  beaker,  lead-lined  or  iron 
pot  until  the  temperature  reaches  ioo°-i3o°  C.,  when 
200  gms.  of  coarsely  powdered  spirit  soluble  indulin  is 
added  a  little  at  a  time  with  constant  stirring,  maintain- 


FIG.  25. 

ing  the  temperature  throughout  between  100°  and  130°. 
When  all  the  indulin  has  been  dissolved,  as  shown  by  the 
absence  of  lumps,  dilute  a  drop  of  the  sulphonated  mix- 
ture in  hot  water  in  a  test  tube,  add  a  few  drops  of  dilute 
caustic  soda  solution,  and  warm.  A  complete  solution 
of  the  color  shows  that  sulphonation  is  accomplished. 
If  there  is  still  some  insoluble  color,  continue  heating  the 
sulphonated  mixture  until  a  sample  is  completely  soluble 
in  the  dilute  alkali. 

To  free  the  sulphonated  indulin  mixture  of  excess 
sulphuric  acid,  wash  by  pouring  into  6  liters  of  water. 
Agitate  well,  let  settle,  and  filter  .on  a  suction  plate.  Break 


ORGANIC  PREPARATIONS 


61 


up  the  hard  cake  thus  obtained  in  3  Hters  of  water,  agitate, 
and  filter  again. 

The  next  step  is  neutralization  to  produce  the  water 
soluble  sodium  salt.  To  the  insoluble  sulphonation  product 
of  the  indulin  add  30  per  cent  caustic  soda  solution,  a 
little  at  a  time  with  thorough  mixing,  until  a  sample  of 
the  color  is  completely  soluble  in  water.  The  water  soluble 
indulin  paste  is  then  evaporated  to  dryness  on  a  water- 
bath  or  in  a  drying  oven,  and  ground. 

97.  Nigrosine.     (a)  Spirit    Soluble,    Into    a    5-gallon, 


FIG.  26. 

i -inch  thick  cast-iron  kettle  (Fig.  26),  pour  3500  gms.  of 
aniline,  3500  gms.  of  mirbane  oil  (nitrobenzene),  and  4200 
gms.  of  20°  Be.  hydrochloric  acid,  or  its  22°  Be.  equivalent. 
Add  350  gms.  of  iron  filings  and  18  gms.  copper  filings. 
Place  a  woven  asbestos  gasket  on  the  flange,  or  make  one 
by  putting  on  a  thick  layer  of  asbestos  fiber  made  into 
a  stiff  paste  with  water.  Put  cover  in  place  and  clamp 
it  down  tight  with  about  5  strong  clamps.  Connect  to 
a  i -inch  iron  pipe  condenser.  Heat  as  follows: 

Up  to  110°  C.  in  about  one  hour  (a  rise  of  approxi- 
mately i|°  per  minute); 


62      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

Maintain  at  110°  for  three  to  four  hours  to  distill  off 
the  water  in  the  hydrochloric  acid  (about  15  gms. 
should  distill  per  minute) ; 

From  iio°-ii5°  in  three  hours,  keeping  the  flame  under- 
neath very  low.  The  heat  adjustment  will  have 
to  be  very  carefully  made  above  110°. 

From  1 15°- 1 33°  in  three  hours. 

At  133°  for  one  hour. 

From  i33°-i5o°  in  three  hours  (about  6°  per  hour  rise). 

From  i5o°-i7o°  in  one  hour,  and  turn  off  the  gas. 

At  this  point  a  violent  internal  reaction  will  take  place, 
vapors  will  be  given  off,  and  the  temperature  will  rise 
above  195°.  If  the  reaction  fails  to  take  place  at  170° 
heat  slowly  above  that  point  until  the  reaction  starts. 
When  the  vapors  cease  coming  over,  the  batch  is  finished. 
It  is  allowed  to  cool  and  harden.  The  cover  is  then  re- 
moved and  the  brittle  mass  is  chopped  out  This  is 
crude  spirit-soluble  nigrosine  contaminated  with  iron, 
copper,  and  organic  impurities,  subsequently  removed  by 
sulphonation  and  washing. 

Should  it  be  impossible  to  complete  the  heating  in 
one  run,  it  may  be  discontinued  at  any  point  before 
the  final  reaction  and  started  again  at  another  time.  It 
is  advisable,  however,  to  at  least  reach  above  the  110° 
point.  In  reheating,  care  must  be  taken  to  heat  slowly. 

(b)  Water  Soluble.  If  the  heating  has  been  properly 
controlled,  the  crude  melt  will  sulphonate  in  a  mixture 
of  three  times  its  weight  of  sulphuric  acid  (sp.  gr.  1.84)  and 
three- tenths  of  its  weight  of  fuming  sulphuric  acid;  other- 
wise, the  sulphonation  must  be  carried  out  with  three  times 
its  weight  of  fuming  acid  entirely.  The  fuming  acid 
costs  more  and  is  more  difficult  to  handle. 


ORGANIC  PREPARATIONS 


63 


To  test  for  strength  of  sulphonating  acid  required, 
slowly  stir  25  gms.  of  the  ground  nigrosine  into  75  gms. 
of  sulphuric  acid  and  7.5  gms.  of  fuming  acid  in  a  beaker, 
keeping  at  ioo°-no°.  After  it  has  completely  dissolved, 
heating  and  stirring  are  continued  for  one  hour.  About 
one-fourth  of  the  sulphonated  mass  is  poured  into  150  cc. 
of  water,  stirred,  filtered,  and  washed.  A  particle  of  the 
color  is  added  to  a  test  tube  of  water,  heated,  and  a  few 
drops  of  dilute  caustic  soda  solution  added  to  slight  alka- 
linity. Complete  solubility  of  the  color  indicates  that  this 
strength  of  acid  may  be  used.  If  a  precipitate  forms  on 
the  addition  of  the  caustic,  it  shows  that,  although  the 
spirit-soluble  nigrosine  has  dissolved  in  this  strength  of 
acid,  it  has  not  sulphonated,  and  therefore,  it  will  be 
necessary  to  use  the  straight  fuming  acid  for  sulphonation. 

To  sulphonate,  heat  12.6  kgms.  of  sulphuric  acid  and 
1.26  kgms.  of  fuming  acid  to  ioo°-no° 
in  a  4-  to  5-gal.  iron  vessel,  heated  by 
gas  or  lead  steam  coil,  preferably  pro- 
vided with  an  iron  stirrer  and  hood  (Fig. 
27).  Slowly  and  with  constant  stirring, 
add  4.2  kgms.  of  the  coarsely  ground 
nigrosine,  taking  care  that  the  mass  does 
not  foam  over.  When  all  the  color  is  in, 
heat  and  stir  for  about  two  more  hours 
and  test  a  sample  for  complete  sulphona- 
tion by  pouring  into  water,  washing  an^  neutralizing  as 
directed  in  testing  for  the  strength  of  sulphonating  acid. 
If  color  is  not  entirely  soluble  in  water,  heat  and  agitate 
for  two  more  hours,  or  until  soluble.  If  the  fuming  sul- 
phuric acid  must  be  used,  4.2  kgms.  of  color  will  take 
12.6  kgms.  of  acid. 


FIG.  27. 


64      LABORATORY   GUIDE  OF  INDUSTRIAL  CHEMISTRY 

To  free  excess  acid,  wash  by  slowly  stirring  the 
sulphonated  mass  into  30  gals,  of  water.  Agitate  for 
one-half  hour;  allow  to  settle  for  about  six  hours  or  more, 
and  siphon  off  the  clear  liquid.  Add  15  gals,  of  water, 
agitate,  and  settle  again.  Siphon  off.  Add  15  gals,  of 
water  for  the  last  washing  and  agitate  while  the  color 
is  being  filtered  on  a  suction-plate  or  through  a  filter 
press. 

The  next  step  is  neutralization  to  form  the  water- 
soluble  sodium  salt.  To  the  wet  cake  from  the  filter  care- 
fully add  a  30  per  cent  caustic  soda  solution,  mixing 
well  until  a  sample  is  completely  soluble  in  water.  It 
is  necessary  to  obtain  a  neutral  or  slightly  alkaline 
condition. 

The  wet,  water  soluble  nigrosine  may  be  dried  in  a 
hot-air  oven  or  in  a  vacuum  drier.  Water  soluble  nigro- 
sine comes  on  the  market  in  small  lumps  the  size  of  a 
pea.  If  desired  in  a  powdered  form,  it  can  be  easily  ground. 

Note.  This  method  of  making  nigrosine  is  only  one  of 
many  for  the  preparation  of  this  color,  and  together  with 
indulin  has  been  furnished  by  one  of  my  former  students, 
Mr.  Aaron  Schreiman. 

98.  Methyl  Violet  T.  B. 


Mix  well  in  a  mortar  875  gms.  of  sodium    chloride 
and   50  gms.   finely  powdered  copper  sulphate,   and  add 


ORGANIC  PREPARATIONS  65 

a  solution  of  40  gms.  of  phenol  in  10  cc.  of  water. 
Stir  well.  One  hundred  gms.  of  dimethyl  aniline  is  now 
added  and  the  mixture  transferred  to  a  round-bottom 
flask  and  heated  on  the  water-bath  for  eight  hours  at 
55°  C.  The  product  is  poured  out  into  a  porcelain  basin 
and  allowed  to  cool.  In  order  to  free  it  from  phenol 
and  salt,  it  is  broken  up  and  added  gradually  to  3  liters 
of  boiling  water  containing  milk  of  lime,  prepared  from 
40  gms.  of  CaO  and  200  cc.  of  water.  After  heating  until 
no  more  lumps  are  present,  the  mixture  is  allowed  to  settle, 
and  the  clear  solution  of  salt  and  calcium  phenate  de- 
canted. The  residue  of  copper  oxide,  methyl  violet,  and 
calcium  sulphate  is  washed  again  by  decantation,  and 
finally  filtered. 

In  order  to  get  rid  of  the  copper  oxide,  the  precipitate 
is  boiled  with  dilute  sulphuric  acid,  and  sodium  sul- 
phate (free  from  chloride)  added  to  precipitate  the  dye, 
which  is  filtered  and  washed.  The  precipitated  violet  is 
subsequently  dissolved  in  water  and  reprecipitated  with 
salt. 

99.  Fast  Red  B.     (Bordeaux  B). 


OH    S03Na 


SO3Na 


Seventy-one  and  a  half  gms.  of  a-naphthylamine  is 
dissolved  in  1500  cc.  of  water,  150  cc.  of  concentrated 
hydrochloric  acid  added,  and  the  temperature  reduced 


66      LABORATORY   GUIDE  OF  INDUSTRIAL  CHEMISTRY 

to  about  40°  C.  by  the  addition  of  ice.  Thirty-six  gms. 
of  sodium  nitrite  dissolved  in  a  small  quantity  of  water  is 
now  poured  in.  The  diazo  solution  thus  obtained  is  poured 
into  a  solution  of  175  gms.  of  R  salt  in  2000  cc.  of  water, 
previously  made  alkaline  by  the  addition  of  50  gms.  of 
caustic  soda,  and  cooled  to  15°  C.  After  standing  for 
at  least  one  hour,  the  solution  is  warmed  to  80°  C.  and 
common  salt  added  until  the  dyes  tuff  is  precipitated. 
The  latter  is  then  filtered  off  and  dried. 
100.  Chrysamine  G. 

COONa  COONa 


Thirty-seven  gms.  of  benzidine  is  dissolved  in  500  cc. 
of  hot  water,  containing  100  cc.  of  concentrated  hydrochloric 
acid,  and  then  cooled  with  ice  to  5°  C.  The  cold  solution 
of  the  benzidine  chloride  is  next  tetrazotized  with  30  gms. 
of  sodium  nitrite  in  a  small  quantity  of  water.  The 
solution,  after  addition  of  the  sodium  nitrite,  should  be 
clear  and  give  a  blue  color  with  starch-iodide  paper. 

Sixty-two  gms.  of  salicylic  acid  is  dissolved  in  500  cc. 
of  cold  water  to  which  has  been  added  20  gms.  of  caustic 
soda.  To  this  alkaline  solution  the  above  tetrazo  solu- 
tion is  added  and  the  whole  stirred  mechanically  for  six 
hours.  During  the  stirring,  25  gms.  more  of  caustic 
soda  is  gradually  added.  The  coloring  matter  is  slowly 
precipitated  and  is  eventually  filtered  off  and  dried. 

101.  Sulphur  Black  T.  (Constitution  Unknown.)  Five 
hundred  gms.  of  sodium  sulphide  is  dissolved  in  750  cc. 
of  water,  and  to  this  solution  is  added  180  gms.  of  sul- 


ORGANIC  PREPARATIONS  67 

phur  and  120  gms.  of  orthodinitrophenol.  This  mixture 
is  then  boiled  for  eighteen  hours  on  a  sand-bath,  in  a 
flask  provided  with  reflux  condenser.  The  flask,  after 
heating,  is  removed  from  the  sand-bath  and  a  stopper 
inserted,  arranged  with  glass  tube  extending  to  the  bottom 
of  the  liquid.  Another  glass  tube  is  also  placed  in  the 
cork  in  such  a  manner  that  it  may  be  connected  with  the 
suction  pump.  A  stream  of  air  is  now  drawn  through 
the  liquid  until  a  test  sample  on  filter  paper  shows  a  color- 
less rim.  The  precipitate  is  then  filtered  off  and  dried. 


CHAPTER  IV 
DYEING   OF  TEXTILE   FIBERS 

102.  Dyeing  is  the  process  of  precipitating  coloring- 
matter  upon  or  within  the  substance  of  a  body  by  chem- 
ical action.    The  solution  may  be  neutral,  acid,  or  alkaline, 
according  to  the  nature  of  the  material  and  of  the  dyestuff 
employed. 

103.  There  are  two  general  classes  of  dyestuffs,  namely, 
natural   and   artificial.     Owing   to   the   large   number   of 
coal-tar   colors   on   the   market,   however,    and   the   ease 
with  which  they  are  applied,  the  natural  colors  have  been 
steadily  replaced,  until    to-day  logwood    and   fustic    are 
practically  the  only  ones  that  are  of  any  importance  in 
the  trade. 

104.  For   practical    reasons,    the    coal-tar   colors    are 
divided  generally  into  the  following  groups: 

1.  Acid  dyes. 

2.  Basic  dyes. 

3.  Dyes  of  the  eosine  group. 

4.  Sub stan tine  dyes. 

5.  Mordant  dyes. 

6.  Developed  dyes. 

7.  Sulphur  dyes. 

8.  Spirit  colors. 

105.  Acid    Dyes.     These  colors  are  chiefly  used  for 
wool  dying,  but  they  are  also  applied  to  silk,  and  with 

68 


DYEING  OF  TEXTILE  FIBERS  69 

few  exceptions  the  dyeing  takes  place  in  an  acid  bath. 
Although  of  little  interest  for  cotton,  they  are  of  great 
importance  for  jute.  The  commercial  dyestuffs  consist 
of  the  alkali  or  lime  salts  of  the  color  acid.  Thus, 
in  the  case  of  wool  dyeing,  the  wool  acts  as  a  base, 
combining  with  the  color  acid  to  form  an  insoluble 
compound. 

106.  Basic  Dyes.     These   colors  are   chiefly  used  on 
mordanted  cotton.     Large  quantities  are  also  consumed 
in  silk  dyeing,  and  a  considerable  amount  of  a  few  brands 
for    wool.      They    are    also    extensively    used    for    jute. 
Basic  dyes  are  the  salts  of  colorless  bases,  that  is,  the 
color   does   not   appear    until    the   salt   is  formed.      The 
commercial   dyestuffs   are    usually  salts   of   acetic,  oxalic, 
nitric,    sulphuric,    or    hydrochloric '  acid,    and    most    of 
them  are  soluble  in  water.      In  the    process  of    dyeing, 
these    compounds    decompose,     setting    free    the    acid, 
while  the  base  combines  with    the    acid    constituent    of 
the  animal  fiber,  or  with  the  acid  mordant  in  the   case 
of    vegetable    fiber,    thus    producing    the    color    on   the 
fabric. 

107.  Dyes  of  the  Eosine  Group.     In  the  textile  indus- 
try these  colors  are  used  for  wool  and  silk,  also  to  a  small 
extent  for  cotton.     They  are  derived  from  fluorescein  by 
the   action   of   halogens.     To   this   group   belong   cosine, 
erythrosine,   phloxine,   rose  bengal,   and  uranine.     All  of 
these  dyestuffs  possess  a  yellowish-green  fluorescence. 

108.  Substantive  Dyes.     These  are  very  largely  con- 
sumed for  dyeing  cotton  and  unions;    they  are  also  used 
for  wool  and  silk.     They  are  sometimes  called   "  direct 
dyes,"  owing  to  the  fact  that  they  dye  cotton  direct  with- 
out mordanting.      To   this   group   belong    the   benzidine 


70      LABORATORY   GUIDE  OF  INDUSTRIAL   CHEMISTRY 

dyes,    primuline,     Congo,    diamine,    benzo    and    amino 
colors. 

109.  Mordant  Dyes.     These  comprise  a  great  variety 
of    coloring-matters,    both   natural    and    artificial,    which 
are  dyed  on  all  fibers  by  the  aid  of  metallic  mordants. 
Many  of   these  dyes    are  polygenetic,  and    they  possess 
the  property  of  forming  insoluble  color  lakes  with  metallic 
oxides.     The  usual  method  employed  is  to  mordant  the 
goods  before  passing  them  into  the  dye-bath,  which  usually 
contains   nothing    but   the   color.      In    a   few   cases   the 
mordant  and   color  are  introduced  into  the   same  bath, 
whereas,  in  the  process  known  as  "  padding,"  the  goods 
are  first  run  in  the  color  and  subsequently  in  the  mor- 
dant. 

110.  Developed    Dyes.     Under    this   heading   are   in- 
cluded two  different  methods  of  developing,  viz. : 

(a)  The  production  of  dyestuffs  from  substances  which 
possess  no  dyeing  quality  themselves,  but  which  can  be 
changed    into   dyestuffs  by  a  chemical   reaction    taking 
place  on  the  fiber. 

(b)  The  production  of  new  products  by  further  devel- 
oping dyestuffs  so  as  to  change  their  shade  and  properties. 

The  first  of  these  processes  is  represented  by  the  pro- 
duction of  aniline  black;  the  second,  by  the  process  of 
diazotizing,  both  of  which  will  be  taken  up  later. 

111.  Spirit  Colors.     These  dyes  are  insoluble  in  water 
but   soluble   in   alcohol.     They   are   sometimes   used   for 
dyeing  silk,  and,  when  dissolved  in  acetone,  for  printing 
silk  and  cotton,  also  for  making  colored  varnish. 

112.  General  Instructions  for  Dyeing.     In  conducting 
dye-tests,  it  will  prove  advantageous  to  make  up  the  solu- 
tions as  follows: 


DYEING  OF  TEXTILE  FIBERS  71 

Natural  dyestuffs  and  tannins .  .  10  per  cent  solution 

Coal-tar  colors i  per  cent  solution 

Acids 10  per  cent  solution 

Salts .  10  per  cent  solution 

Soap i  per  cent  solution 

Provide  yourself  with   a  reel,   a  convenient  form  of 
which  is  represented  in  the  illustration,  Fig.  28.     As  all 


FIG.  28. 


tests  are  conducted  on  the  weight  of  the  material,  it  is 
necessary  to  determine  the  number  of  yards  required  to 
give  a  skein  of  definite  weight.  The  following  list,  however, 
may  prove  useful: 

Columbia  knitting  worsted. .   20  yds.  weigh    5  gms. 

Cotton  yarn,  22-ply 100  yds.  weigh    5  gms. 

Spun  silk,  2-ply 100  yds.  weigh    5  gms. 


72      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

By  noting  the  example  given  below,  a  clear  idea  may 
be  gained  as  to  the  use  of  the  solutions  mentioned  and 
the  reason  for  having  the  skeins  of  definite  weight. 

113.  Example.     Prepare  a  dye-bath  with  2  per  cent  of 
Congo  red,  2  per  cent  of  sodium  carbonate,  and  20    per 
cent  of  Glauber's  salt,  using  six  5-gm.  skeins    of    cotton 
yarn,  boil  for  half  an  hour.     Remove,  rinse,  and  dry. 

Thus:  6X5=3Ogms. 
2  per  cent  of  30  gms.  is  0.6  gm. 

20  per  cent  of  30  gms.  is  6  gms. 

As  the  Congo  red  is  a  i  per  cent  solution,  it  will 
require  60  cc. 

As  the  sodium  carbonate  is  a  10  per  cent  solution,  it 
will  require  6  cc. 

And  as  the  Glauber's  salt  is  a  10  per  cent  solution,  it 
will  require  60  cc. 

The  dye-tests  are  best  made  in  porcelain  beakers 
placed  in  brine  to  secure  a  uniform  temperature.  The 
skein  is  suspended  on  a  glass  rod  and  the  position  changed 
at  least  once  in  five  minutes  during  the  time  of  dyeing. 

On  completing  the  tests  the  skeins  are  hung  up  to  dry, 
twisted,  and  mounted  as  follows: 

Place  each  end  of  the  skein  over  the  two  middle  fingers, 
.twist  until  tight,  then  bring  the  right-hand  loop  under 
the  wrist  and  up  through  the  loop  in  the  left.  Now, 
holding  the  two  loops,  stretch  the  skeins  out  straight 
and  allow  them  to  curl  together.  In  this  manner  a  very 
tight  and  even  skein  is  secured.  These  skeins  should  then 
be  mounted  on  cardboard  by  sewing  through  from  the 
back,  catching  down  the  threads  on  the  under  side  in 
such  a  way  that  it  does  not  show  from  the  front. 

114.  Wool.     In  the  study  of  dyes  and  dyeing,  we  will 


DYEING  OF  TEXTILE   FIBERS  73 

first  take  up  the  natural  mordant  colors,  that  may  be 
used  for  wool. 

One  of  the  oldest  and  most  important  dyes  for  wool 
is  logwood,  or  Campeachy  wood,  which  is  the  wood  of  a 
larch  tree  growing  abundantly  in  the  West  Indies,  Mexico, 
and  parts  of  Central  America.  It  is  imported  in  logs 
weighing  about  400  Ibs.  The  fresh  wood  is  colorless,  or 
nearly  so,  and  contains  a  glucoside,  composed  of  hema- 
toxyline  and  sugar.  It  is  cut  into  chips  or  rasped.  These 
chips  are  then  digested  with  hot  water,  and  the  solution, 
on  evaporation,  gives  the  logwood  extract  of  the  market. 

Formerly,  for  wool  dyeing,  the  chips  were  allowed  to 
oxidize  before  extraction,  but  now  this  is  accomplished 
in  the  solution,  and  the  product  is  known  as  hematine 
paste  or  crystals. 

Logwood  is  a  mordant  color,  by  which  we  mean  that 
the  color  is  produced  only  by  bringing  it  in  contact  with 
some  metal.  In  this  way  a  combination  takes  place 
with  the  formation  of  an  insoluble  lake. 

115.  The  simplest  method  of  dyeing  with  logwood  con- 
sists in  applying  the  coloring  matter  and  mordant  at  the 
same  time.  The  disadvantage  of  this  method  is  that 
part  of  the  lake  produced  is  only  superficially  held  by  the 
fiber,  and  also  much  color  is  lost  by  being  precipitated 
in  the  bath.  It  is  used  to  some  extent,  however,  on 
account  of  the  cheapness  of  the  color. 

To  illustrate  this  method,  dye  a  5-gm.  skein  of  woolen 
yarn  with  10  per  cent  of  hematine  logwood  paste,  3  per  cent 
of  ferrous  sulphate,  and  i  per  cent  of  oxalic  acid  in  400  cc. 
of  water,  keeping  it  at  a  quiet  boil  for  one  hour.  In  all 
dyeing  experiments  it  is  essential  to  keep  the  solution 
at  a  constant  volume  by  adding  hot  water  from  time 


74      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

to  time.     Care  should  also  be  taken  that  the  skeins  are 
turned  several  times  during  the  dyeing  operation, 

116.  The   usual  method   of   dyeing  with   logwood   or 
other  mordant  color  is  to  mordant  the  fiber  before  intro- 
ducing  it   into    the   dye-bath.     The   wool   is,    therefore, 
boiled  in  the  solution  of  a  metallic  salt  to  which  has  been 
added  some  acid  or  acid  salt,  the  latter  acting  as  an  assist- 
ant to  the  mordant.     The  wool,  being  of  a  basic  character, 
acts  chemically  upon  the  metallic  salt,  fixing  the  metal  in 
such  a  way  that  it  cannot  be  washed  out. 

117.  Boil  three  5-gm.  skeins  of  wool  for  half  an  hour 
in  a  solution  containing  5  per  cent  of  alum,  3  per  cent 
of  oxalic  acid,  and  400  cc.  of  water.     Dye  one  of  these 
skeins  at  boiling  with  5  per  cent  of  hematine  powder  in 
400  cc.  of  water.     On  removing  the  first  skein,  a  second 
one  should  be  introduced  and  run  for  half  an  hour  to  see 
if  the  color  has  been  exhausted.     The  third  skein  is  dyed 
with  5  per  cent  of  fustic  extract,  being  run  for  one  hour. 

118.  The  most  important  mordant  for  wool  is  chromium, 
generally  applied  as  the  dichromate,   together   with    an 
acid  or  acid  salt.     The  assistant  in  this  case  may  be  either 
sulphuric  acid,  oxalic  acid,  tartaric  acid,  potassium  bitar- 
trate,  or  potassium  bisulphate.     The  color  produced  by 
logwood  depends  both  upon  the  mordant  and  the  assist- 
ant employed,  and  is  an  example  of  that  class  of  dyestuffs 
known  as  polygenetic.    Monogenetic  colors,   on  the  other 
hand,  are  those  which  give  only  one  color,  no  matter  what 
kind  of  mordant  is  used. 

119.  To  demonstrate  the  application  of  chrome  and 
sulphuric  acid,  mordant  two  5-gm.  skeins  of  worsted  with 
3  per  cent  of  sodium  dichromate  and  ij  per  cent  of  sul- 
phuric acid  in  400  cc.  of  water,  boiling  for  if  hours.     The 


DYEING  OF  TEXTILE   FIBERS  75 

sulphuric  acid  liberates  the  chromic  acid,  which,  in  turn, 
unites  with  the  wool,  producing  a  chromate  of  wool. 
By  this  means,  some  of  the  chromic  acid  is  reduced;  the 
largest  part,  however,  remains  unreduced,  oxidizes  the 
coloring  matter  of  the  logwood,  and  combines  with  it 
to  produce  a  blue-black  lake.  In  addition  to  the  above, 
the  sulphuric  acid  prevents  the  metallic  salt  from  decom- 
posing too  readily  and  thus  aids  in  producing  even  and 
fast  colors. 

Introduce  one  of  the  skeins,  which  has  been  mordanted 
as  above,  into  a  bath  containing  10  per  cent  of  hematine 
paste  and  'boil  for  one  hour,  running  the  second  skein 
as  an  exhaust  test. 

120.  Mordant  two  more  skeins  of  worsted,  as  in  119, 
then  dye  with  10  per  cent  of  hematine  paste  and  \  per 
cent  of  alizarine  yellow.     It  will  be  noticed  that  a  deep 
black  is  the  result  as  compared  with  the  shade  produced 
by  straight  hematine. 

121.  Mordant  two  5-gm.  skeins  of  worsted  yarn  with 
3  per  cent  of  sodium  dichromate  and  2  per  cent  of  oxalic 
acid  in  400  cc.  of  water,  boiling  for  one-half  hour.     Dye 
one  of  these  skeins  with  10  per  cent  of  hematine  paste  for 
one-half   hour,   following   with   the   second   skein   as   an 
exhaust. 

122.  Mordant  four  5-gm.  skeins  of  worsted  yarn  with 
3  per  cent  of  sodium  dichromate  and  i\  per  cent  of  cream 
of  tartar  in  400  cc.  of  water,  boiling  for  one  hour.     Dye 
one  of  the  skeins  with  10  per  cent  of  hematine  paste,  boiling 
for  one  hour;    follow  with  a  second  skein  as  an  exhaust. 
Dye  a  third  skein  with  10  per  cent  of  hematine  paste  and 
i  per  cent  of  alizarine  yellow,  following  with  an  exhaust. 

123.  Mordant  four  5-gm.  skeins  of  worsted  yarn  with 


76      LABORATORY   GUIDE   OF   INDUSTRIAL   CHEMISTRY 

3  per  cent  of  sodium  dichromate  and  i  per  cent  of  sul- 
phuric acid  in  400  cc.  of  water,  boiling  for  one  hour.  Dye 
one  skein  with  each  of  the  following  dyestuffs: 

Alizarine  Red  Alizarine  Yellow 

Alizarine  Orange  Alizarine  Blue 

The  alizarine  colors  were  originally  derived  from  madder, 
but  are  now  prepared  synthetically.  In  working  with 
them  the  mordanted  material  should  be  entered  cold,  the 
temperature  slowly  raised  to  the  boil,  and  the  boiling 
continued  for  one  hour. 

124.  The  simplest  method  of  dyeing  wool  is  that  which 
employs  the  acid  colors.     This  process  may  be  considered 
as  a  lake  formation  in  which  the  animal  fiber  acts  the  part 
of  a  base,  while  the  color  plays  the  part  of  an  acid.     In 
conducting  these  tests,  the  skeins  are  entered  hot,  or  even 
at  the  boil,  and  the  boiling  continued  for  one  hour,  using 
20  per  cent  of  Glauber's  salt,  3  per  cent  of  sulphuric  acid, 
and  i  per  cent  of  color,  except  in  the  case  of  blacks,  when 
as  high  as  7  per  cent  may  be  necessary. 

Some  acid  colors: 

Fast  Red  Acid  Violet  (all  brands) 

Patent  Blue  Orange  (all  brands) 

Scarlet  6R,  2R,  etc.  Naphthol  Yellow  S 

Naphthol  Brown  O  Naphthylamine  Black 

Acid  Magenta  Naphthylamine  Blue 

Acid  Rhodamine  Naphthol  Red 

125.  Basic  colors  are  used  to  a  slight  extent  on  wool, 
the  process  being  somewhat   similar   to   that  with   acid 
colors,  except  that  3  per  cent  of  acetic  acid  (30  per  cent) 
is  employed  in  place  of  the  sulphuric  acid. 


DYEING  OF  TEXTILE  FIBERS  77 

Some  basic  dyestuffs: 

Auramine  Safranine 

Induline  Scarlet  Phosphine 

Janus  Red  Janus  Blue 

Janus  Black  Janus  Brown 

Bismarck  Brown  Methylene  Blue 

Malachite  Green  Methyl  Violet 

126.  Silk.     Raw   silk,   as  it   appears   on   the  market, 
is  heavily  coated  with  a  glue-like  substance  which  must 
be  removed  before  the  fiber  can  be  subjected  to  the  dye- 
ing operations.     This  is  accomplished  by  "  boiling  off  " 
in  a  strong  soap  solution,  and  is  also  known  as  "degum- 
ming  "  or  "  stripping."     When  boiled  off,   silk  will  lose 
about  25  per  cent  of  its  weight.     Should  the  scouring  be 
limited    to    a    loss    of    only    10   to    15    per    cent    of   its 
weight,    it    is    termed    "soupling";    when   silk   is    given 
only  a  very  slight  scouring,  the  result  is  known  as  "  ecru." 
The  quality  of  soap  employed  is  usually  about  30  per  cent 
of  the  weight  of  the  fiber,  and  the  liquor  remaining   is 
used  for   dyeing    purposes,  being  known  as  "  boiled-off 
liquor." 

127.  Silk  resembles  wool  in  its  behavior  toward  mor- 
dants and  dyestuffs,  except  that  it  has  less  affinity  for 
acid  colors  and  greater  affinity  for  basic  dyestuffs. 

128.  Boil  off  ten  5-gm.  skeins  of  silk  with  30  per  cent 
of  Marseilles  soap,  boiling  for  one-half  hour  with  a  dilu- 
tion of  1000  cc. 

129.  Prepare  a  dye-bath  with   100  cc.  of  the  boiled- 
off  liquor  (from  128)  and  300  cc.  of  water.     Make  acid 
with  sulphuric  acid.     Raise  the  temperature  to  100°  F. 
and  enter  the   boiled-off  skein.     After  turning  the  skein 


78      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

several  times,  withdraw  it  and  add  i  per  cent  of  the  dye- 
stuff.  Raise  to  140°  F.  and  finally  finish  at  the  boil, 
turning  several  times  during  the  operation. 

The  following  dyestuffs  are  suitable  for  the  above: 

Naphthol  Yellow  Orange 

Fast  Red  Acid  Violet 

Acid  Green  Palatine  Black 

130.  Prepare   a    dye-bath  with   100    cc.   of   boiled-off 
liquor  (from  128)  and  300  cc.  of  water.     Make  acid  with 
acetic  acid.     Raise  the  temperature  to  100°  F.  and  enter 
the  boiled-off   skein.     Then  add  i  per  cent  of  the  dye- 
stuff.     Raise  to  140°  F.,  and  finally  finish  at  the  boil. 

Suitable  dyestuffs  are: 

Auramine  Rhodamine 

Eosine  Magenta 

Methyl  Violet  Victoria  Green 

131.  Cotton.     Vegetable  fibers  like  cotton  consist  prin- 
cipally of  cellulose,  a  very  inactive  substance  chemically. 
When  treated  with  dilute  mineral  acids,  there  is  little  action 
until  the  fiber  becomes  dry,  when  it  will  weaken  or  fall 
to  a  powder.     This  destructive  action  is  more  marked  at 
elevated  temperatures  and  is  called  carbonization,  because 
the  powder  formed,  hydro-cellulose,  is  usually  black,  and 
was  thought  to  be  carbon.     For  this  reason,  cotton  cannot 
be  dyed  in  an  acid  bath.     Dilute  alkalies  have  no  action 
on  cotton,  consequently  they  are  employed  in  the  dyeing 
operations. 

132.  Cotton  yarns  or  fabrics  should  always  be  "  boiled 
off  "  or  "  wetted  out  "  before  dyeing.     To  do  this,  the 


DYEING  OF  TEXTILE  FIBERS  79 

stock  should  be  boiled  in  water  containing  2  gins,  of  soda 
ash  per  liter,  and,  when  thoroughly  wet,  placed  in  fresh 
water  until  needed.  It  is  well  to  boil  out  at  least  i  dozen 
skeins  before  starting  the  tests  to  be  applied  to  cotton. 

133.  Prepare  a  dye-bath  with  2  per  cent  of  dyestuff 
(substantive  color),  i|  per  cent  of  sodium  carbonate,  and 
30  per  cent  of  Glauber's  salt,  using    six    5-gm.  skeins. 
Boil  for  half  an  hour,  remove,  rinse,  and  dry. 

Suitable  dyestuff s  are: 

Congo  Red  Benzo  Purpurine 

.    Primuline  Dianil  Red 

Benzo  Orange  Oxy  Diamine  Brown 

Diamine  Black  Oxy  Diamine  Black 

134.  Prepare  a  dye-bath  as  in   133,  leaving  out  the 
sodium  carbonate,  and  dye  in  it  six  skeins  of  worsted  yarn. 
It  will  be  noticed  that  the  wool  has  taken  up  more  color, 
indicating   that  vegetable   fibers  have   less  than  affinity 
for   dyestuff  s   do   animal  fibers.     The  reason  for   leaving 
out   the    sodium    carbonate  is   that   wool    is    soluble    in 
alkaline  solutions.     The  object  of   adding  the   Glauber's 
salt  is    to   make    the   dye   more   insoluble  and  cause  it 
to  unite  better  with  the  fiber. 

135.  In  judging  the  value  of  a  dyestuff,  several  tests 
are  always  applied  to  determine  its  quality  when  sub- 
mitted to  normal  wearing  conditions. 

136.  Into  a  dye-pot  containing  boiling  water  introduce 
a  skein  of  the  dyed  cotton  yarn,  and,  at  the  same  time, 
enter  a  skein  of  undyed  cotton.     Boil  for  fifteen  minutes. 

137.  Repeat  test  136,  using  dyed  woolen  yarn    with 
undyed  woolen.     It  will  be  noticed   that  the  color  has 


80      LABORATORY   GUIDE  OF  INDUSTRIAL  CHEMISTRY 

been  removed  from  the  cotton  to  a  far  greater  extent 
than  from  the  wool,  and  that  the  undyed  cotton  yarn  has 
become  colored.  This  loss  of  color  is  known  as  bleeding, 
and  in  washed  goods  would  be  very  objectionable. 

138.  Prepare  a  soap  solution  with  4  gms.  of  soap  in 
400  cc.  of  water,  and  heat  to  about  60°  C.     Now  work 
in  this  solution  a  skein  of  dyed  cotton  yarn  together  with 
an  undyed  skein.     At  the  end  of  ten  minutes  note  any 
change  that  may  have  taken  place.     This  test  represents 
the  process  of  washing,  so  that  the  less  a  color  is  stripped, 
the  better  is  the  dyestuff. 

139.  Many  colors,  when  exposed  to  sunlight,  undergo 
a  change  or  are  said  to  fade.     This  can  be  readily  shown 
by  placing  a  skein  of  dyed  cotton  in  a  wooden  frame 
so  arranged  as  to  protect  half  of  the  skein  and  leave  the 
other  half  exposed  to  the  action  of  the  sun.     At  the  end 
of  two  days  open  the  frame  and  note  the  results. 

140.  Expose  a  skein  of  dyed  woolen  yarn  at  the  same 
time  and  compare  the  two  skeins. 

141.  Dyed  goods  are  often  subjected  to  acid  conditions 
and  to  perspiration,  so  that  it  is  necessary  to  know  what 
action   is   to  be  expected  in   such  cases.     To   determine 
this,    introduce    a  skein    of  dyed  cotton  yarn  into   a    10 
per  cent  solution  of  acetic  acid  and  work  for  ten  minutes. 
Wring  out   the   skein,   wash,   and   dry  it.     If   the   color 
changes,  it  is  not  fast  to  acids. 

142.  Test  a  skein  of  dyed  woolen  yarn  in  the  same 
manner. 

143.  It    sometimes    happens    that   a  test    for    alkali 
is  necessary.     To  accomplish  this,  the  dyed  cotton  skein 
is  worked  for  ten  minutes  in  a  hot  2  per  cent  solution  of 
sodium  carbonate. 


DYEING  OF  TEXTILE  FIBERS  81 

144.  Wool  is  soluble  in  hot  alkali,  but,  before  it  dis- 
solves, a  peculiar  action,  known  as  "  felting,"  is  brought 
about.     To  show  this,  work  a  skein  of  dyed  woolen  yarn 
in  a  hot  2  per  cent  solution  of  sodium  carbonate  for  ten 
minutes. 

145.  Some  colors  can  be  used  in  a  cold  solution,  which, 
on  certain  fabrics,  is  quite  advantageous.     To  carry  out 
this  test,  stir  up  the  dyestuff  with  an  equal  weight  of 
caustic  soda  (70°  Tw.)  and  dissolve  the  whole  in  boiling 
water.     Now  prepare  a  bath  with  cold  water  to  which 
has  been  added  i  per  cent  of  soap,  i  per  cent  of  color, 
and  20  per  cent  of  Glauber's  salt.     Use  cotton  for  test. 

Some  suitable  dyestuffs  are: 

Cotton  Yellow  G  Oxamine  Red 

Pyramine  Orange  Oxamine  Fast  Claret 

Cotton  Rubine  Oxamine  Brown 

146.  Spirit  soluble  colors  are  sometimes  used  for  dyeing 
cotton  and  linen  fabrics  such  as  lace  or  other  fine  materials. 
To  illustrate,  prepare  a  bath  with  Bismarck  Brown  base, 
using  i  gm.  of  color  to  100  cc.  of  alcohol.     Keep  in  a  well- 
stoppered  bottle.     Into  a  dye  pan  place  200  cc.  of  alcohol, 
add  50  cc.  of  dye  solution,  and  work  in  this  a  5-gm.  skein 
of  cotton  yarn.     (The  solution  in  the  dye-bath  may  be 
saved  for  further  use.) 

147.  Oil  soluble  colors  are  also  used  to  some  extent 
for  laces.     They  are  prepared  by  rubbing  up    a  spirit 
soluble  color  in  oleic  acid  and  then  dissolving  the  resulting 
paste  in  benzine.     To  demonstrate  this  method,  rub  up 
i  gm.  of  Methyl  Violet  base  with  5  gms.    of    oleic    acid 
and  dissolve  in  100  cc.  of  benzine.     Now  make  up  a  dye- 
bath  with  200  cc.  benzine,  using  i  per  cent  of  the  color, 


82      LABORATORY   GUIDE  OF  INDUSTRIAL  CHEMISTRY 

and   dip   in   it  a  5-gm.    skein   of   unboiled   cotton  yarn, 
working  for  five  minutes,  remove  and  dry. 

148.  Mercerization.    When  cotton  is  treated  with  a 
concentrated    solution    of    caustic    soda    it    contracts    in 
length,   becoming  heavier  and   stronger.     This  was  first 
noticed  by  John  Mercer  in   1850,   and  hence  is  known 
as  "  mercerization."     The  chemical  change  taking  place  is 
due  to  the  formation  of  the  compound  Ci2H20Oio-2NaOH. 
This  body  when  washed  decomposes  with  the  production 
of  Ci2H20Oio-H20,  cellulose  hydrate,  or  mercerized  cotton. 

149.  Mercerized  cotton  has  a  much  stronger  affinity 
for  substantive  colors  than  ordinary  cotton,  and  also  has 
a  greater  combining  power  with  mordants. 

150.  To  200  cc.  of  water  add  40  gms.  of  caustic  soda 
and  allow  to  cool.     Cut  a  piece  of  unbleached  cotton  cloth 
about  5  inches  long  by  i  inch  wide.     Wet  out  and  immerse 
in  the  above  solution  for  five  minutes.     Remove,  wash 
thoroughly,  and  dry.     Note  the  loss  in  measurement  due 
to  shrinkage. 

151.  Work  four  boiled-off  skeins  of  cotton  yarn  in  the 
above  caustic  soda  solution  for  five  minutes.     On  removing 
the  skeins,  wash  them  well  in  running  water,  then  with 
water   containing   a   little    acetic   acid,    and    again   with 
fresh   water.     It   will   be   noticed   that   the   skeins   have 
shrunk  about  25  per  cent  of  their  length.     If,  however, 
these  skeins  had  been   stretched  during   the  process  of 
mercerization,  a  high  finish  or  gloss  would  have  resulted. 
The  best  grade  of  cotton  for  mercerization  is  that  known 
as  Egyptian. 

152.  Dye  a  skein  of  mercerized  cotton  with  J  per  cent 
of  Benzo  Purpurine  and   10  per  cent  of  Glauber's  Salt 
in  400  cc.  of  water,  boiling  for  one-half  hour. 


DYEING  OF  TEXTILE  FIBERS  83 

153.  Dye  a  skein  of  boiled-off  unmercerized  cotton  in 
the  same  manner.     It  will  be  noticed  that  the  mercer- 
ized skein  takes  up  more  color  and  that  the  color  is  faster 
to    washing    than    that   produced    on    the    unmercerized 
yarn. 

154.  Mordant  two  skeins  of  mercerized  cotton  by  boil- 
ing for  thirty  minutes  with  4  per  cent  of  tannic  acid, 
using  400  cc.  of  water. 

155.  Mordant  two    skeins  of  unmercerized,  boiled-off 
cotton  in  the  same  manner. 

156.  Dye  a  skein  of  mercerized  cotton,  which  has  been 
mordanted  with  tannic  acid,  in  a  bath  containing  J  per 
cent  of  Malachite  Green,  using  400  cc.  of  water  at  50° 
C.,  and  work  for  one-half  hour. 

157.  Dye  a  skein  of  unmercerized  cotton,  which  has 
been   mordanted  with  tannic   acid,  in   the   same   manner 
as    in   156.     Note  any  difference  in  the  depth  of  shade 
obtained. 

158.  Malachite   Green  is  an   example  of  basic  color 
that  is  a  direct  dye  for  wool  but  not  for  cotton.     These 
dyes  can  be  dyed  on  cotton  only  by  the  aid  of  tannic 
acid. 

159.  Mordant  five  5-gm.  skeins  of  cotton   yarn    with 
5  per  cent  of  sumach  in  400  cc.  of  water,  boiling  for  fifteen 
minutes,  or  until  "  wetted  out,"  and  allow  to  stand  one 
hour. 

160.  Dye   one   skein,   which  has   been  mordanted   as 
above  (159),  with  each  of  the  following,  using  2  per  cent 
of  the  dyestuff,  temperature  I2o°-i4o°  F: 

Auramine  Malachite  Green  (all  brands) 

Safranine  T  extra  Methyl  Violet  R 


84      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

161.  Mordant  five  5-gm.  skeins  of  cotton    yarn    with 
5  per  cent  of  cutch  in  400  cc.  of  water  in  the  same  manner 
as  above. 

162.  Dye  one  skein  which  has  been  mordanted  as  above 
(161),  with  each  of  the  following,  using  i  per  cent  of  the 
dyestuff: 

Auramine  Malachite  Green  (all  brands) 

Safranine  T  extra  Methyl  Violet  R 

These  tests  with  sumach  and  cutch  illustrate  the  ap- 
plication of  the  numerous  commercial  sources  of  tannic 
acid  to  dyeing  and  printing. 

The  examples  given  under  tannic  acid  mordants  serve 
to  illustrate  a  large  class  of  basic  colors  applied  to  cotton, 
and,  as  they  all  act  in  practically  the  same  manner,  it 
will  not  be  necessary  to  give  more  along  this  line,  except 
to  include  a  list  for  those  desiring  to  make  a  more  ex- 
haustive study  of  the  subject. 

A  few  other  basic  colors  are: 

Rhodamine  (all  brands)  Magenta 

Brilliant  Green  Cryst  Janus  Red  B 

Cotton  Green  Janus  Yellow 

New  Fast  Blue  Naphthol  Blue  R  T 

Phosphine  Bismarck  Brown 

163.  Metallic  Tannates.     By  subjecting  cotton,  which 
has  been  mordanted  with  tannic  acid,  to  a  metallic  salt 
treatment,  an  insoluble  metallic  tannate  is  produced,  pos- 
sessing a  greater  affinity  for  basic  colors  than  the  tannic 
acid  alone.     The  process  of  converting  the  tannic  acid 
into  this  condition  is  known  as  "  fixing."     The  salts  of 
antimony,  tin,  titanium,  and  iron  are  the  ones  most  fre- 
quently employed. 


DYEING  OF  TEXTILE  FIBERS  85 

164.  Mordant  two  skeins  of  cotton  yarn  with  5  per 
cent  of  tannic  acid  in  400  cc.  of  water.     Bring  to  a  boil 
and  allow  to  stand  for  one  hour.     Fix  one  of  the  skeins 
by  working  for  twenty  minutes  in  a  bath  containing  2 
per  cent  of  tartar  emetic  in  400  cc.  of  water. 

165.  Prepare  two  dye-baths  with  i  per  cent  of  Methylene 
Blue  in  400  cc.  of  water.     Enter  a  skein  of  the  mordanted 
yarn  in  each,  raise  to  70°  C.,  and  keep  at  this  temperature 
for  one-half  hour.     Squeeze  out  the  excess  of  color,  dye, 
and  compare  results. 

166.  Developed  Dyes.     Many  of  the  substantive  dyes 
may  be  applied  to  cotton  in  the  usual  manner  and  then 
changed  by  chemical  treatment  into  other  colors.     These 
are  usually  much  faster  to  washing  and  other  agents  than 
the  original  color.     The  process  employed  is  known  as 
"  diazotizing  "   and   "  developing,"   and   consists  in   sub- 
jecting the  dyed  skein  to  the  action  of  nitrous  acid,  then 
subsequently  to  a  developing  agent.     The  colors  which 
respond  to  this  treatment  are  those  containing  the  amino 
group  NH2.     This  amino  group,   through  the  action  of 
nitrous  acid,  becomes  converted  into  the'"diazo"  group 
N  :  N.    As  these  diazonium  compounds  are  very  unstable, 
the  operation  must  be  conducted  in  the  cold  and  away 
from  direct  sunlight.     The  change  which  takes  place  may 
be  represented  by  the  following  equation: 

RNH2HC1+HN02=RN  :  NCI. 

As  soon  as  the  cotton  is  diazotized,  it  should  be  immediately 
transferred  to  a  developing  solution.  The  function  of  the 
0-naphthol  (or  other  developer)  is  to  combine  with 
the  unstable  diazo  body  to  give  the  new  and  permanent 
coloring  matter.  This  bath  should  also  be  kept  cold. 


86      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

The  reaction  of  the  developer  may  be  illustrated  by  the 
following  equation: 

RN  :  NCl+CiCH7OH=RN  :  NCi0H6OH+HCl. 

Some  diazo  colors  are: 

Sulphine  Dianil  Black 

Oxamine  Blue  Dianil  Ogene  Sky  Blue 

Oxamine  Violet  Oxy  Diamine  Ogene 

Dianil  Brown  Primuline 

167.  Enter  five  skeins  of  boiled-off  cotton  yarn  into  a 
bath  containing  2  per  cent  of  primuline,  25  per  cent  of 
salt,  and  2  per  cent  of  sodium  carbonate  in  400  cc.  of 
water.     Boil  for  one-half  hour,  remove,  and  wash. 

168.  To  diazotize  these  skeins  enter  five  of  them  into 
a  bath  containing  4  per  cent  of  sodium  nitrite,  50  per  cent 
of  hydrochloric  acid  with  400  cc.  of  cold  water.     Work 
for  ten  minutes,  remove,  and  pass  rapidly  to  the  following 
solutions. 

169.  Hang  one  of  the  diazotized  skeins  in  the  sunlight 
for  half  an  hour  and  develop  as  in  (a)  of  1 70  below. 

170.  Prepare  three  baths  as  follows,  and  enter  a  skein 
of  the  diazotized  cotton  in  each.     Work  for  ten  minutes, 
wash,  and  dry. 

(a)  One  per   cent  of  /3-naphthol   and   i   per   cent   of 
sodium  hydroxide  in  400  cc.  of  cold  water. 

(b)  One  per  cent  of  resorcin  and  2  per  cent  of  sodium 
hydroxide  in  400  cc.  of  cold  water. 

(c)  Two  per  cent  of  a-naphthol  and  4  per  cent   of 
sodium  hydroxide  in  400  cc.  of  cold  water. 

171.  Removal  cf  Stains.     Fruit  or  vegetable  stains  may 
be  removed  usually  by  washing  with  dilute  oxalic  acid  or 


DYEING  OF  TEXTILE  FIBERS  87 

vinegar.     Dilute    hydrochloric    acid    will    also    give    the 
same  result. 

Most  colors  may  be  removed  by  bleaching  powder 
and  an  acid.  The  best  method  is  to  dip  the  goods  into 
the  solution  or  emulsion  of  the  chloride  of  lime  and,  after 
working  for  two  or  three  minutes,  ring  out,  then  dip  in 
a  3  per  cent  solution  of  oxalic  acid  and  wash  thoroughly. 
Hydrochloric  or  sulphuric  acid,  or  even  vinegar,  may  be 
used.  This  is,  of  course,  for  white  goods  which  have  been 
stained  with  colors  or  inks.  Stains  may  be  removed 
from  the  hands  in  the  same  manner. 

Another  easy  method  of  removing  stains  from  the 
hands  is  to  wash  in  a  i  per  cent  solution  of  potassium 
permanganate,  then  in  a  2  per  cent  solution  of  oxalic  acid, 
and  rinse  thoroughly. 

Stains  caused  by  tannic  acid,  iron  inks,  and  iron  rust 
can  usually  be  taken  out  with  oxalic  acid  or  potassium 
acid-oxalate.  Many  vegetable  stains  disappear  after  simply 
soaking  in  tepid  water. 

Mordant  colors,  as  a  rule,  are  more  difficult  to  dis- 
charge from  the  hands  or  fabrics,  but  can  be  removed 
by  the  following  treatment: 

Place  in  the  hand  about  2  teaspoonfuls  of  chloride 
of  lime  and  cover  with  about  twice  as  much  sodium 
carbonate.  Just  moisten  (do  not  wet)  with  water  and 
work  into  a  paste.  When  the  paste  becomes  warm 
rub  over  the  hands  or  fabric  like  soap.  Work  until 
nearly  dry,  and  then  rinse.  Follow  this  treatment 
with  a  strong  solution  of  sodium  bisulphite  and,  without 
rinsing,  by  a  strong  solution  of  oxalic  acid.  Wash  well, 
and  dry. 

Grease  spots,  oils,  paints,  varnishes,  and  tar  may  be 


88      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

removed  by  washing  or  rubbing  with  a  cloth  saturated 
with  either  naphtha,  benzene,  ether,  chloroform,  carbon 
bisulphide,  carbon  tetrachloride,  turpentine,  or  common 
kerosene. 

172.  The   Sulphur  Dyestuffs  on  Cotton.— The  colors 
belonging  to  this  group  are  absorbed  by  cotton  in  a  bath 
containing  sodium  sulphide. 

The  bath  is  prepared  by  boiling  a  solution  containing 
from  2  to  10  per  cent  of  dyes  tuff,  2  to  3  per  cent  of  sodium 
carbonate,  5  to  10  per  cent  of  sodium  sulphide,  and  10 
to  20  per  cent  of  sodium  chloride,  or  Glauber's  salt.  The 
fiber  is  entered  into  the  boiling  bath  and  worked  until 
finished,  about  i|  hours.  It  is  very  essential  that,  after 
dyeing,  the  cotton  should  be  thoroughly  washed  before 
drying. 

Examples.  Immedial  Black,  15  per  cent;  sodium  sul- 
phide, 10  per  cent;  soda  ash,  5  per  cent;  Glauber's  salt, 
20  per  cent.  Immedial  Yellow,  5  per  cent;  sodium  sul- 
phide, 5  per  cent;  soda  ash,  5  per  cent;  Glauber's  salt, 
5  per  cent.  Immedial  Dark  Blue,  20  per  cent;  sodium 
sulphide,  20  per  cent;  soda  ash,  10  per  cent;  Glauber's 
salt,  20  per  cent.  Katigen  Indigo,  2  R  L  extra,  10  per 
cent;  sodium  sulphide,  20  per  cent;  soda  ash,  6  per  cent; 
Glauber's  salt,  50  per  cent.  Katigen  Black  T  extra,  7.5 
per  cent;  sodium  sulphide,  15  per  cent;  soda  ash,  8  per 
cent;  Glauber's  salt,  60  per  cent. 

173.  Vat  Colors  on  Cotton  and  Wool.     The  most  im- 
portant dyes  tuff  of  this  class  is  Indigo,  produced  upon 
the  fiber  by  first  treating  with  an  alkaline  solution  of 
Indigo  white,  which,  on  oxidation  in  the  air,  is  recon- 
verted into  the  blue.     The  term  "  vat "  applies  to  the 
vessel  employed  for  dissolving  the  Indigo,  and  also  to 


DYEING  OF  TEXTILE  FIBRES  89 

the  solution  itself,  which  may  be  prepared  by  the  aid  of 
various  reducing  agents. 

174.  The  Zinc  Lime  Vat. 

Indigo  M.L.G.  powder  (or  25  gms.  paste),     10  gms. 
Zinc  dust,  10  gms. 

Quicklime,  30  gms. 

Mix  the  zinc  dust  with  150  cc.  of  water  at  50°  C.; 
add  the  Indigo  and  then  the  lime  with  constant  stirring. 
The  whole  is  left  to  stand  for  six  hours,  but  is  stirred 
from  time  to  time.  The  reduction  is  complete  when  a 
drop  of  the  solution,  placed  on  a  sheet  of  glass,  runs  off 
as  a  yellow  liquid  that  oxidizes  in  the  air  in  the  course 
of  forty-five  to  fifty  seconds. 

The  reduced  solution  is  then  diluted  with  500  cc.  of 
water  and  the  cotton  fiber  dyed  in  it  by  thoroughly  soak- 
ing. It  is  then  wrung  out,  and  dried  in  the  air,  the  process 
being  repeated  until  the  requisite  shade  is  obtained. 

175.  The  Sulphate  of  Iron  Vat.    By  following  the  same 
directions  as  above  this  bath  may  be  prepared,  using 

Indigo  M.L.B.  powder,      10  gms. 
Ferrous  sulphate,  50  gms. 

Quicklime,  60  gms. 

176.  The  Hydrosulphite    Vat   (for  cotton).      This  vat 
is  based  on  the  property  of  hydrosulphurous  acid,  H2S2O4, 
of  forming  with   Indigo   a   colorless,   double   compound, 
soluble  in  alkalies,  and  decomposed  by  the  weakest  oxi- 
dation, Indigo  blue  being  thereby  liberated. 

For  practical  use  the  sodium  salt  of  hydrosulphurous 


90      LABORATORY   GUIDE   OF   INDUSTRIAL    CHEMISTRY 

acid,  Na2S2O4,  is  prepared  by  allowing  zinc  dust  to  act 
on  sodium  bisulphite  in  a  tightly  closed  vessel,  the  mix 
ture  being  kept  stirred  and  cooled.  The  reaction  is 
usually  complete  within  four  or  five  hours.  The  hydro- 
sulphite  solution  is  rendered  slightly  alkaline  with  milk 
of  lime,  in  order  to  diminish  its  instability,  and  is  then 
ready  for  use.  The  procedure  is  as  follows: 

Sodium  bisulphite  solution  71.4°  Tw.,  100    parts 

Cold  water,  225    parts 

and  in  the  course  of  half  an  hour, 

Zinc  dust  stirred  into  this  solution  3^  parts 

The  whole,  which  is  stirred  from  time  to  time,  is  left 
to  stand  for  four  or  five  hours,  and  then  mixed  with 

Lime,     nj  parts,  slaked  in 
Water,  30    parts. 

After  allowing  the  sediment  to  settle,  the  clear  solu- 
tion is  decanted  and  7  parts  caustic  soda  solution,  36° 
Tw.,  added. 

The  hydrosulphite  solution  is  now  ready  for  use.  It 
should  stand  at  i9°-2o°  Tw.  and  be  kept  in  a  tight  bottle 
in  a  dark  room. 

177.  Preparation  of  Dye  Vat. 

Indigo,  10  gms.,  mixed  with 

Hot  water,  30  gms. ;  to  this  mixture  add 

Caustic  soda,  76°  Tw.,  85  gms.  and  stir  well;  after 

heating  to  50°  C.,  add 
Hydrosulphite  solution,  20°  Tw.,  250  gms.  and  keep 

the  temperature  at  50°  C. 


DYEING  OF  TEXTILE  FIBERS  91 

In  the  course  of  the  reduction  which  takes  place,  and 
which  is  tested  in  the  usual  way  with  a  sheet  of  glass, 
more  hydrosulphite  solution  is  added  in  several  portions. 
The  reduced  Indigo  ought  to  run  off  fiom  the  sheet  of 
glass  as  a  yellow  liquid  which  oxidizes  in  twenty  to  thirty 
seconds. 

The  cotton  fiber  is  then  dyed  in  the  same  manner  as 
indicated  in  the  case  of  the  zinc  vat. 

178.  The  Hydrosulphite  Vat  (for  wool).     The  process 
is  essentially  the  same,  except  that  the  caustic  soda  must 
be  replaced  by  milk  of  lime  in  sufficient  amount  to  produce 
an  alkaline  reaction. 

179.  Turkey  Red  upon  Cotton.  The  name  "  turkey-red  " 
is  applied  to  the  color  produced  upon  cotton  by  the  aid 
of  alizarine,  alumina,  lime,   and   fatty  acid   compounds. 
This  fatty  acid  compound,  known  as  "  Turkey- red  Oil," 
is  prepared  by  treating  olive  or  castor  oil  with  concen- 
trated sulphuric  acid,  usually  3  parts  of  acid  to  10  parts 
of  oil. 

The  acid  is  slowly  poured  into  the  oil  with  constant 
stirring,  and  the  whole  then  allowed  to  stand  until  a 
sample  of  the  product  dissolves  completely  in  water, 
whereupon  it  is  poured  into  water  and  washed  with  a 
solution  of  sodium  chloride  until  free  from  sulphuric 
acid. 

During  the  process  of  mixing  the  temperature  should 
not  be  allowed  to  rise  above  40°  C.  Sometimes  the  last 
trace  of  acid  is  neutralized  with  ammonia. 

The  production  of  a  good  turkey-red  upon  cotton  can 
be  attained  only  by  practice;  the  directions  given  should, 
however,  yield  fairly  good  results  if  carefully  followed. 

180.  Clearing.     Free  the  cotton    fiber    (5-gm.  skeins) 


92      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

from  grease,  etc.,  by  boiling  in  a  weak  solution  of  sodium 
carbonate;  wring  out  very  thoroughly. 

181.  Oiling.    Without  drying,  enter  into  a  bath  con- 
taining 

Turkey-red  Oil,    10  gms. 
Water,  90  gms. 

and  work  until  thoroughly  soaked.  Wring  out  and  dry 
in  hot-air  cupboard  at  4o°-5o°  C. 

Repeat  this  operation  twice,  drying  between  each  immer- 
sion. 

182.  Alumina   Mordant.    Work   the   fiber   through   a 
bath  of  aluminium  acetate,  9°  Tw.;    wring  out  and  dry 
at  4o°-5o°  C. 

Repeat  this  treatment. 

183.  Chalking.     Enter  the  cotton  into  a  bath  containing 

Chalk,     6  gms. 
Water,     i  liter 

at  30°-40°  C.  Stir  well  for  about  half  an  hour,  and  then 
wash  thoroughly  in  clean  water.  It  is  unnecessary  to 
dry  the  cotton  before  dyeing. 

184.  Dyeing.    Stir  the  dyestuff  (15  per  cent  alizarine 
paste)  into  the  water  and  enter  the  skein  at  2o°-25°  C. 
Work  the  skeins  at  this  temperature  for  about  twenty 
minutes,  and  then  heat  up  so  that  in  about  half  an  hour 
the  temperature  rises  to  60°  C.     Keep  at  this  point  for 
about  an  hour,  then  wring  well  and  dry. 

185.  Steaming.     Steam  the  dried  cotton  for  one  hour 
at  a  pressure  of  15  Ibs.,  or  for  two  hours  without  pressure; 
then  wash  well. 


DYEING  OF  TEXTILE  FIBERS  93 

186.  Brightening.    Brighten   the   dyed*  material   in   a 
closed  apparatus  at  a  pressure  of  5  Ibs.     Work  in  a  solu- 
tion of  4.5  gms.  of  soap  in  i  liter  of  water;    leave  the 
cotton  in  it  for  ten  minutes  and  wash  well. 

187.  Colors    Produced    Directly  upon    the  Fiber  by 
Oxidation.    Aniline   black,    the   typical   member   of   this 
group,  is  produced  directly  on  the  cotton  fiber  by  the 
oxidation  of  aniline,  and  the  two  following  methods  will 
suffice  to  indicate  the  manner  in  which  dyestuffs  of  this 
kind  are  formed: 

(a)  One-bath  black. 

The  bath  should  contain 

Aniline,  5  per  cent 

Hydrochloric  acid,  12  per  cent 
Bichromate  of  soda,  6  per  cent 
Copper  sulphate,  5  per  cent. 

The  cotton  should  be  entered  into  the  bath  and  worked 
for  one  hour;  then  the  bath  should  be  raised  to  boiling 
during  another  hour,  and  the  fiber  worked  at  this  tem- 
perature for  another  half  hour;  wash  and  dry. 

(b)  Oxidation  black. 


Aniline  hydrochloride, 

126  gms. 

Water, 

300  cc. 

Chlorate  of  potash, 

40  gms. 

Acetate  of  alumina,  21.6°  Tw., 

150  gms. 

Ammonium  chloride, 

5.  7  gms. 

Copper  sulphate, 

3  gms. 

and  the  whole  made  up  to  i  liter. 

The  fiber  is  thoroughly  impregnated  in  this  solution, 


94      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

wrung  out  and  dried.     It  is  then  worked  for  half  an  hour 
at  60°  C.  in  a  bath  containing 

Bichromate  of  soda,  2.5  per  cent 

Aniline  hydrochloride,  -5  per  cent 

Sulphuric  acid,  .8°  Tw.,        .2  per  cent 

and  then  washed  and  dried. 

188.  Cotton  Printing,  (a)  General  Remarks.  The  var- 
ious methods  of  printing  depend  upon  the  use  of  a  color 
solution  to  which  a  thickening  agent  has  been  added.  In 
most  cases  fixing  agents  (acids,  etc.),  or  substances  with 
which  the  dyestuffs  can  form  lakes  (tannic  acid,  chrome 
compounds)  are  added,  and  the  material  is  printed  with 
this  mixture.  The  process  is  usually  carried  out  on  the 
roller  or  cylinder  machine.  After  printing,  the  goods  are 
dried,  or  they  are  dried  and  slightly  moistened  again. 
They  are  then  steamed  with  or  without  pressure.  In  the 
case  of  many  dyestuffs  the  correct  development  of  shade 
and  proper  fixation  take  place  during  this  process.  This 
is  followed  by  an  after  treatment  with  fixing  agents,  the 
details  of  which  depend  upon  the  goods  in  question  and 
the  requirements.  The  goods  are  then  rinsed,  etc. 

(b)  Thickening  Agents.  In  order  to  obtain  good  results 
it  is  necessary  to  choose  a  suitable  thickening  agent. 
Below  are  given  several  that  may  be  considered  typical 
of  their  group. 

Tragacanth  Solution.  This  is  used  as  a  thickening 
for  printing  basic  colors  on  cotton  and  silk  and  is  suitable 
for  producing  ground  colors  and  very  delicate  light  shades. 

Gum  tragacanth,      \  Ib.  gum 
Water,  i  gallon 


DYEING  OF  TEXTILE  FIBERS  95 

mix  and  stir  at  intervals  for  some  time.  The  mixture  is 
next  boiled  for  four  to  six  hours,  and  the  water  that  has 
boiled  off  is  replaced,  so  as  to  bring  the  mixture  to  about 
its  original  volume. 

This  is  used  with  an  addition  of  acetic  acid  for  producing 
light  shades  with  basic  colors. 

Acetic  Acid-Starch-Dextrine  Thickening: 

Wheat  starch,  24  gms. 

Dextrine,  20  gms. 

Water,  52  gms. 

Tragacanth  solution,  5  per  cent,  40  gms. 
Acetic  acid,  9°  Tw.,  60  gms. 

Glycerine,  4  gms. 

Boil  ten  minutes. 

Weight  of  cold  thickening,  176  gms. 
A  soft  smooth  thickening  suitable  for  printing  Methylene 
Blue  on  cotton. 

Egg  Albumen  Thickening: 

Egg  albumen,  40  gms. 
Cold  water,  38  gms. 
Ammonia  liquor,  2  gms. 

are  mixed  together  and  allowed  to  stand  for  twelve  hours, 
after  which  the  mixture  is  sieved  or  passed  through  calico. 
This  serves  as  a  thickening  for  the  substantive  and  pig- 
ment colors.  As  a  rule  it  is  used  only  for  clear,  light  shades. 
Casein  Thickening: 

Powdered  casein,     15  gms. 
Cold  water,  84  gms. 

Ammonia  liquor,        i  gm. 


96      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

This   thickening  is  used   instead   of   albumen   for   cheap 
articles. 

(c)  General  Methods  of  Preparing  Basic  Colors: 

Color,  10  gms. 

Acetic  acid,  9°  Tw.,  100  gms. 
Water,  130  gms. 

Thickening,  700  gms. 

Tannic  acid,  30  gms. 

Acetic  acid,  9°  Tw.,   30  gms. 

When  preparing  the  printing  pastes,  the  dyestuff  is 
either  dissolved  in  water  and  a  little  acetic  acid,  and  this 
solution  then  added  to  the  thickening,  which  has  already 
been  prepared,  or  the  thickening  agents  are  mixed  in 
the  color  solution  and  boiled  with  the  necessary  amount 
of  water  and  acetic  acid.  In  both  cases,  the  tannic  acid 
necessary  for  the  formation  of  the  color  lake  is  dissolved 
in  an  equal  weight  of  acetic  acid  and  then  slowly  stirred 
into  the  printing  paste,  but  not  until  this  has  cooled  down. 

After  printing,  the  pieces  are  dried,  steamed  for  one- 
half  to  one  hour  without  pressure,  and  then  worked  for 
five  to  ten  minutes  in  a  lukewarm  solution  containing 
100  gms,  of  tartar  emetic  to  every  40  liters  of  water,  in 
order  to  fix  the  color  completely.  They  are  then  rinsed 
and  soaped. 

(d)  General  Method  of  Preparing  the  Colors  of  the  Eosine 
Group: 

Color,  20  gms. 

Hot  water,  230  gms. 

Thickening,  600  gms. 

Acetate  of  alumina,  15°  Tw.,  50  gms. 

Acetate  of  magnesia,  15°  Tw.,  100  gms. 


DYEING  OF  TEXTILE  FIBERS  97 

Print,  dry,  steam  for  one-half  hour  at  one-half  atmos- 
pheric pressure,  but  do  not  rinse. 

(e)  General  Method  for  Substantive  Dyes  with  Albumen: 

Color,  20  gms. 

Hot  water,  250  gms. 

Glycerine,  30  gms. 

Egg  albumen  i  *  i,  700  gms. 

stir  the  mixture  well. 

Print,  dry,  and  steam  for  one-half  hour  at  5  Ibs.  pressure, 
and  rinse. 

Those  who  desire  to  make  a  more  exhaustive  study  of 
this  subject  should  refer  to  the  literature  published  by 
the  various  color  companies. 


CHAPTER  V 
PIGMENTS  AND   LAKES 

189.  Pigments.  Pigments  are  mineral  or  organic  bodies, 
usually  insoluble  in  water,  oils,  or  other  neutral  solvents. 
They  are  used  to  impart  color  to  a  base  by  admix- 
ture with  its  substance.  The  color  of  a  pigment  depends 
upon  the  amount  and  kind  of  light  it  reflects.  It  is 
necessary  that  the  pigment  be  opaque  in  order  to  give 
good  "  covering  power,"  that  is,  it  should  entirely  con- 
ceal the  surface  to  which  it  is  applied. 

The  chief  pigments  are  given  in  the  following  table : 


Whites 
White  Lead 
Lead  Sulphate 
Lead  Oxychloride 
White  Zinc 
Zinc  Sulphide 
Barytes 
Gypsum 
Whiting 
Lithopone 

Yellows 

Chrome  Yellow 
Yellow  Ocher 
Cadmium  Yellow 


Blues 

Ultramarine 
Prussian  Blue 
Smalt 

Cobalt  Blue 
Copper  Blue 
Indigo 

Chinese  Blue 
Violet 
Ultramarine 

'Reds 

Red  Lead 
Chrome  Red 
Red  Ocher 

98 


Greens 
Ultramarine 
Brunswick  Green 
Chrome  Green 
Guignet's  Green 
Copper  Greens 
Arsenic  Green 
Violet  Lake 


Blacks 
Lamp  Black 
Ivory  Black 
Bone  Black 


PIGMENTS  AND  LAKES  99 


Yellows 
Orpiment 
Litharge 
Gamboge 
Indian  Yellow 

Reds 
Venetian  Red 
Vermilion 
Realgar 
Antimony  Red 
Carmine 

Blacks 
Graphite 

Orange  Browns 

Orange  Mineral  Umbers 

Chrome  Orange  Vandyke  Brown 

Antimony  Orange  Sepia 

Many  other  pigments,  both  natural  and  artificial,  are 
in  use,  but  as  they  do  not  have  a  distinctive  color,  they 
are  not  included  in  the  above  classification.  For  a  de- 
tailed description  of  these  pigments  consult  references  in 
the  Manual  of  Industrial  Chemistry. 

The  preparation  of  some  typical  pigments  will  be 
taken  up,  illustrating  the  method  of  handling  artificial 
colors. 

190.  Prussian  Blue.  Dissolve  1000  gms.  of  sulphate 
of  iron  (ferrous)  in  15  liters  of  water  and  add  50  gms. 
of  hydrochloric  acid.  To  this  solution  add  a  solution  .of 
1000  gms.  of  ferrocyanide  of  potassium  and  50  gms.  of 
hydrochloric  acid  in  30  liters  of  water.  Now  slowly  add 
to  the  mixture  400  gms.  of  bleaching  powder,  when  the 
white  precipitate  will  be  changed  to  a  blue  one.  To 
hasten  the  oxidation,  it  is  well  to  boil  with  open  steam  for 
a  short  time.  This  pigment  being  finely  divided  is  slow 
to  settle  at  first,  and  should  be  allowed  to  stand  for  several 
days.  When  the  Prussian  Blue  has  settled  somewhat, 
the  top  liquid  is  siphoned  off,  and  the  tank  again  filled 


100    LABORATORY   GUIDE  OF  INDUSTRIAL   CHEMISTRY 

with  water.  This  process  of  washing  is  continued  until 
the  test  of  the  wash-water  shows  only  slight  traces  of 
sulphates.  The  pigment  is  next  passed  into  the  filter 
press,  washed  again,  removed,  dried,  and  ground  to  a 
fine  powder  in  the  ball  mill. 

191.  Red  Oxide.    Place  about  1000  gms.  of  ferrous 
sulphate  in  an  iron  crucible  and  heat  until  nearly  all  of 
the  fumes  of  sulphuric  anhydride  are  given  off.     Then 
add  100  gms.  of  slaked  lime  and  heat  until  uniform  color 
is  obtained. 

192.  Vermilion.     Put  300  gms.  of  mercury  and   114 
gms.  of  sulphur  into  a  mortar  and  triturate  Until  the 
ingredients    are    thoroughly    incorporated.     Dissolve    76 
gms.   of   caustic  potash  in   a    14-inch   evaporating   dish, 
using  600  cc.  of  water,  and  add  the  contents  of  the  mortar. 
Heat  to  45°  C.  and  maintain  this  temperature  for  several 
hours,  stirring  very  thoroughly  at  frequent  intervals  and 
keeping  the  volume  of  water  constant  for  the  first  two 
hours.     Regulate  the  temperature  so  that  it  will  not  exceed 
45°  C.,  nor  fall  below  40°.     In  the  course  of  two  or  three 
hours  the  mass  becomes  brown  and  then  gradually  turns 
a  bright  red.     When  the  desired  vermilion  color  is  ac- 
quired, usually  after  six  or  eight  hours,  wash  by  decan- 
tation  until  free  from  alkali.     Filter  by  means  of   the 
press,  and  dry  on  glass  plates  at  not  over  45°. 

193.  Antimony    Vermilion.     One    hundred    and    forty 
gms.   of  sodium  thiosulphate  is  dissolved  in   250  cc.   of 
water,  making  a  solution  of  40°  Tw.     One  hundred  cc.  of 
anitmony  chloride  is  mixed  with  40  cc.   of  water  and 
added  to  the  thiosulphate  placed  in  a  casserole.    This  is 
slowly  heated,  and  when  the  red  color  is  developed,  it  is 
filtered. 


PIGMENTS  AND  LAK&S  'JU  '  101 

194.  Scheele  Green.     Dissolve  150  gms.  of  arsenious 
oxide  in  1000  cc.  of  water  containing  200  gms.  of  sodium 
carbonate.     Next  dissolve   150  gms.   of  copper  sulphate 
in  2000  cc.  of  water,  and  when  both  solutions  are  ready, 
mix   them    together,    allow    them    to    settle,    wash,    and 
filter. 

195.  Chrome    Yellow.     Dissolve    2000    gms.    of    lead 
acetate  in  8  liters  of  water  and  filter  if  necessary.     Then 
dissolve   1550  gms.  of  sodium  dichromate  in  8  liters  of 
water  and  mix  the  two  solutions.     Wash  by  decantation, 
filter,   and  dry.     If  all  of  the  color  is  not  precipitated, 
add  a  little  more  lead  actate. 

196.  Chrome  Red.     Weigh  out  500  gms.  of  lead  ace- 
tate and  175  gms.  of  sodium  dichromate;    dissolve  each 
separately  in  10  liters  of  water,  then  mix  the  two  solu- 
tions.    Allow  the  precipitate  of  chrome  yellow  to  settle 
out,  pour  off  the  supernatant  liquor,  add  a  solution  of 
75  gms.  of  caustic  soda  in  500  cc.  of  water,  and  boil  for 
about  one-half  hour,   or  until   the  yellow  has  assumed 
a  red  color,  then  filter,  wash,  and  dry. 

197.  Chrome  Orange.     Dissolve  500  gms.  of  lead  ace- 
tate in  10  liters  of  water;  next  weigh  out  125  gms.  of  sodium 
dichromate  and   125  gms.  of  sulphate  of  soda  and  dis- 
solve in  10  liters  of  water.     Mix  the  two  solutions  together 
and  allow  the  precipitate  to  settle.     Pour  off  the  clear 
liquor,   then  add  a  solution  of  50  gms.  of  caustic  soda 
in  i  coo  cc.  of  water,  boil  the  mixture  for  about  twenty 
minutes,  filter,  wash,  and  dry. 

198.  Satin  White.    Weigh  out  800  gms.  of  lime  and, 
after   slaking  with  water,  make  into  a  thin  cream  with 
more  water.     Weigh  out  1700  gms.  of  aluminium  sulphate 
and  dissolve  in  5  liters  of  water.     Mix  the  two  and  heat 


162  'LABORATORY  GUJDE  OF  INDUSTRIAL  CHEMISTRY 

to  a  boil;   then  allow  to  settle.     Decant  the  clear  liquor, 
wash,  and  allow  to  settle.     Filter  and  dry. 

199.  Lithopone.     Into  a  large  crucible  or  muffle  fur- 
nace place   500  gms.   of  barium   sulphate  and  an  equal 
quantity  of  finely  ground  soft  coal.     Place  the  crucible 
in  the  furnace  and  heat  to  dull  redness  until  a  test  sample 
shows  that  the  sulphate  has  been  converted  to  sulphide. 
Remove  the  heat  and,  when  the  mass  has  cooled,  dis- 
solve in  water,  filter  off  the  insoluble  material,  and  con- 
centrate the  nitrate  to  a  density  of  about  15°  Be.    Now 
prepare  a  solution  of  zinc  sulphate  of  about  the  same 
strength  and  add  a  sufficient  quantity  to  combine  with 
the  barium  sulphide  present.     Filter  off  the  precipitate, 
which  consists  of  a  mixture  of  barium  sulphate  and  zinc 
sulphide,   wash  until  free  from  zinc  sulphate,   and  dry. 
The  dry  powder  is  again  placed  in  a  muffle  furnace  or 
crucible  and  heated  to  dull  redness.     While  still  hot,  it 
is  plunged  into  water,  and  the  precipitate  is  filtered  off, 
dried,  and  ground. 

200.  Chrome  Green.     This  is  made  by  heating  chro- 
mium hydroxide. 

201.  Brunswick    Green.     Four    shades    of    Brunswick 
Green  may  be  made  by  using  the  proportions  given  under 
the  following  separate  heads.     In  each  case,  however,  the 
sulphate  of  iron  and  lead  acetate  are  dissolved  in  separate 
vessels  and  added  to  the  suspended  barytes,  whereas  the 
yellow  prussiate  of  potash  and  dichromate  of  soda  may 
be  dissolved  together  and  added  to  the  above  mixture. 

202.  Pale  Brunswick  Green.     One  thousand  gms.  of 
barytes,   130  gms.  of  acetate  of  lead,   10  gms.   sulphate 
of    iron,    10    gms.    potassium   ferrocyanide  and  40  gms. 
dichromate  of  soda. 


PIGMENTS  AND  LAKES  103 

203.  Medium  Brunswick  Green.     One  thousand  gms. 
barytes,  135  gms.  acetate  of  lead,  15  gms.  of  sulphate  of 
iron,    15   gms.   potassium   ferrocyanide,   45   gms.   dichro- 
mate  of  soda. 

204.  Deep  Brunswick  Green.     One  thousand  gms.  of 
barytes,  140  gms.  acetate  of  lead,  20  gms.  ferrous  sulphate, 
20  gms.  of  potassium  ferrocyanide,  45  gms.  of  dichromate 
of  soda. 

205.  Extra    Deep    Brunswick    Green.     One    thousand 
gms.  of  barytes,  100  gms.  acetate  of  lead,  40  gms.  of  ferrous 
sulphate,  40  gms.  of  potassium  ferrocyanide,  and  50  gms. 
of  dichromate  of  soda. 

2C6.  Lakes.  Color  lakes  are  insoluble  compounds 
formed  by  precipitating  suitable  dyestuffs  on  an  insoluble 
base.  This  base  is  similar  in  action  to  the  fibers  in  ordi- 
nary dyeing.  According  to  its  nature,  it  may  assist  in 
the  preparation  of  the  dyestuffs,  or  may  act  merely  as 
a  carrier  for  the  color.  The  physical  condition  of  this 
base  is  also  important,  as  it  affects  the  covering  power, 
cheapness,  and  character  of  the  pigments  produced.  The 
precipitants  used  are  such  chemicals  as  will  render  the 
dyestuffs  insoluble.  Those  ordinarily  employed  are  barium 
chloride,  calcium  chloride,  lead  acetate  or  nitrate,  zinc 
sulphate,  tannic  acid,  etc.  The  lakes  are  precipitated 
according  to  the  particular  directions,  washed,  filtered, 
and  either  dried  or  used  in  pulp  form.  These  lakes  are 
used  for  various  purposes,  and  the  characteristics  must, 
therefore,  be  suitably  varied.  They  are  usually  classified 
according  to  their  method  of  practical  application.  The 
general  classes  are  as  follows :  Colors  for  the  manufacture  of 
lithographic  inks,  paint  colors,  colors  for  kalsomine  or  wall 
finishes,  colors  for  wall-paper  and  coated-paper  surfaces. 


104       LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

207.  Crimson  Lake.     This  is  one  of  the  most  important 
lakes;   and  its  preparation    takes  place  in   three  stages: 
first,  the  preparation  of  the  cochineal  liquor;   second,  the 
preparation  of  the  hydroxide  of  aluminium;    and  third, 
the  combination  of  these  two. 

Weight  out  200  gms.  of  cochineal,  mix  with  2000  cc. 
of  water,  and  boil  for  five  minutes;  add  30  gms.  of  cream 
of  tartar  and  boil  again;  then  add  4  gms.  of  alum,  boil, 
strain,  and  put  into  the  decoction  50  gms.  more  of  cream 
of  tartar.  The  cochineal  liquor  is  ready.  To  prepare  the 
alumina,  weigh  out  420  gms.  of  alum  (or  its  equivalent 
of  sulphate  of  aluminium),  dissolve  in  3000  cc.  of  hot 
water,  and  add  this  to  140  gms.  of  ammonium  carbon- 
ate in  2000  cc.  of  hot  water,  stirring  well;  then  wash 
thoroughly  with  hot  water.  This  alumina  precipitate  is 
next  mixed  with  the  cochineal  liquor  and  the  whole  boiled 
together.  When  the  crimson  lake  is  formed  it  is  filtered 
off,  washed,  and  dried. 

208.  Some  Basic  Colors  Used  for  Lakes.     The  use  of 
basic  colors  in  producing  lakes  depends  upon  their  affinity 
for  acid  radicals  and  is  best  illustrated  by  example. 

209.  Violet   Lake.    Weigh   out    100   gms.    of   barytes 
and  mix  with  500  cc.  of  boiling  water.    Add  to  this  mix- 
ture 2  gms.  of  Methyl  Violet  and  stir  well.    When  the  dye 
has  dissolved,  add  2  gms.  of  tartar  emetic,  then  a  solu- 
tion of  3  gms.  of  tannic  acid  in  100  cc.  of  hot  water.     If 
on   settling,    the    top    liquor   is  highly  colored,  it  is  an 
indication  that  insufficient  tannic  acid  has  been  added. 
If  necessary,   add   more    tannic  acid,  wash,    filter,   and 
dry. 

The  following  lakes  may  be  made  in  a  similar  manner, 
using  the  foregoing  method. 


PIGMENTS  AND  LAKES  105 

210.  Blue  Lake.     One  hundred  gms.  of  barytes,  3  gms. 
tartar  emetic,  3  gms.  Methylene  Blue,  6  gms.  tannic  acid. 

211.  Crimson   Lake    R.     One  hundred  gms.  barytes, 
3  gms.  tartar  emetic,  3  gms.  Safranine,  6  gms.  tannic  acid. 

212.  Brown  Lake.     One  hundred  gms.  of  barytes,  3 
gms.  tartar  emetic,  3  gms.  Bismarck  Brown,  and  4!  gms. 
of  tannic  acid. 

213.  Scarlet  Lake.    One  hundred  gms.  barytes,  3  gms. 
of  tartar  emetic,  i  gm.  Safranine,  2  gms.  Auramine,  and 
4 1  gms.  tannic  acid. 

214.  Some  Acid  Colors  Used  for  Lakes.     The  following 
is  a  list  of  acid  colors  adapted  for  the  manufacture  of 
lakes  precipitated  with  barium   chloride.     The   example 
given  will  serve  for  the  entire  list. 

Mix  15  parts  of  sulphate  of  aluminium  in  150  parts 
of  water  with  a  solution  of  10  parts  of  Acid  Green  L  in 
100  parts  of  water.  Then  precipitate  with  32  parts  of 
barium  chloride  in  640  parts  of  water.  On  adding  6| 
parts  of  soda  ash  in  65  parts  of  water,  the  alumina  is 
precipitated  in  the  lake,  thus  producing  a  complete  sep- 
aration. 

215.  Reds.    Acid  Magenta;  Azo  Cochineal;  Azo  Crim- 
son S;   Azo  Eosine;  Azo  Phloxine  2  G;   Bordeaux  Extra; 
Brilliant    Crocein    3  B;    Fast  Red  A  B  T;    Ponceau    2 
RL,  5RL. 

216.  Orange.    Orange  II,  B,  G  L;  Mandarine  G. 

217.  Yellow.    Fast  Yellow  Extra;  Fast  Light  Yellow; 
Naphthol  Yellow  S. 

218.  Greens.    Acid    Green    L;     Brilliant  Acid   Green 
6  B ;  New  Acid  Green  3  B  X,  G  X. 

219.  Blues.    Alizarine    Blue    SAP,    SHE;    Cotton 
Blue;   Fast  Blue  Greenish;  Gallocyanin;  Indulin  B. 


106       LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

220.  Violets.    Acid  Violet  4  B,  Extra,    i  R  Ext.  8  B; 
Alkali  Violet;  Fast  Acid  Violet. 

221.  Brown.     Fast  Brown. 

222.  Grays.    Acid  Black  8  B. 

223.  The  Alizarine  Colors  are  very  fast  to  light  and 
water    and    are    extensively   used  in   paints    as    well    as 
lithographic  inks,   etc.     An  example  will  serve  for   the 
class : 

I 

Mix  243  cc.  of  a  10  per  cent  solution  of  aluminium  sulphate, 
125  cc.  of  a  10  per  cent  solution  of  soda  ash. 

Wash  out  three  times.     To  this  add 

30  cc.  of  a  10  per  cent  solution  of  calcium  chloride, 
70  cc.  of  a  10  per  cent  solution  of  sodium  phosphate. 

Wash  twice  and  add 

3  cc.  of  a  10  per  cent  acetic  acid  solution. 

II 

Dissolve  or  stir  up 

Alizarine  red,  30  parts 

Turkey-red  Oil,  5  parts 

Calcium  chloride,  10  per  cent  solution,  5  parts 
Water,  2000  parts 

Add  I  to  II  and  allow  to  remain  for  some  time;  after- 
wards, bring  to  a  boil,  boil  for  several  hours,  or  until 
the  red  is  completely  developed,  wash  and  filter. 

224.  Colors  which  are  Precipitated  with  Lead    Salts. 
Use  30  parts  of  aluminium  hydroxide,  20  parts  of  barytes, 
i  J  parts  of  color,  i  part  of  lead  nitrate. 


PIGMENTS  AND  LAKES  107 

All  acid  colors  given  above;  also,  Uranine,  O  N; 
Eosine,  all  brands;  Erythrosine,  all  brands;  Phloxine,  all 
brands;  Rose  bengal,  GB. 

225.  Crimson    Red.     Dissolve    200    gms.    of    logwood 
extract  in  2000  cc.  of  hot  water  and  add  a  solution  of 
150  gms.  of  sulphate  of  aluminium  in  2000  cc.  of  water. 
Mix  well  and  introduce  65  gms.  of  soda  ash  dissolved  in 
1000  cc.  of  water.    Boil  for  ten  or  fifteen  minutes,  wash, 
and  filter. 

Ferric  chloride  gives  a  bluish  black  precipitate  under 
the  same  conditions;  copper  sulphate,  a  violet  black; 
antimony  chloride,  a  violet;  chromic  acid  or  dichromate, 
a  bronze  black  precipitate. 

By  mixing  various  amounts  of  fustic  or  Persian  berry, 
the  shade  may  be  modified. 

226.  Para  Red.     Dissolve  70  gms.  of  para-nitraniline 
in  2000  cc.  of  water  to  which  has  been  added  150  gms. 
of  concentrated  hydrochloric  acid.     Heat  until  all  of  the 
para-nitraniline  has  dissolved,  cool  below  40°  F.  with  ice, 
and  slowly  add  a  solution  of  50  gms.  of  sodium  nitrate 
dissolved  in  200  cc.  of  water.     Now  stir  in  150  gms.  of 
sodium  acetate  in  1000  cc.  of  water,  and  1000  gms.  of 
blanc  fixe.     While  the  above  is  standing  for  one  hour, 
prepare  a  solution  of  70  gms.  of  /3-naphthol  in  2000  cc. 
of  water,  to  which  has  been  added  30  gms.  of  caustic  soda. 
Cool  with  ice  to  below  40°  F.  and  slowly  add,  with  con- 
stant stirring,  to  the  foregoing  solution.     Filter  off  the  red 
lake  produced,  wash  well,  and  dry  at  a  low  temperature. 

a-naphthylamine  may  be  used  in  place  of  para-nitran- 
iline, and  in  this  case  a  crimson  lake  is  obtained.  Dif- 
ferent shades  may  also  be  secured  by  using  other  reducing 
agents  in  place  of  /3-naphthol. 


CHAPTER  VI 
DRIERS,  VARNISHES,  PAINTS  AND  STAINS 

227.  Driers.  When  some  substances  such  as  acetate 
of  lead,  acetate  of  manganese,  red  lead,  manganese  borate, 
etc.,  are  added  to  paints  and  varnishes,  the  latter  become 
dry  or  hard  much  quicker  than  otherwise.  Linseed  oil, 
mixed  or  heated  with  such  bodies,  dries  much  quicker. 
From  this  fact  has  arisen  the  practice  in  the  manufacture 
of  paints  and  'varnishes  of  adding  so-called  "  driers  " 
for  the  purpose  of  facilitating  the  drying  or  hardening. 

A  very  small  quantity  of  drier  will  cause  the  drying 
of  a  large  quantity  of  oil;  from  0.5  to  i  per  cent  of  the 
weight  of  the  oil  is  usually  sufficient.  Manganese  com- 
pounds are  more  energetic  drying  agents  than  lead  com- 
pounds. Driers  that  dissolve  easily  in  the  oil,  such  as 
linoleates  and  resinates,  are  more  active  than  those  which, 
like  red  lead  or  manganese,  do  not  dissolve  in  the  oil. 

When  raw  linseed  oil  is.  mixed  with  lead  oxide  or 
manganese  borate,  very  little  is  taken  up,  and  the 
rapidity  of  drying  is  not  much  increased;  but,  if  the  oil 
be  heated  with  them,  they  are  more  readily  dissolved,  and 
the  treated  oil  dries  much  more  rapidly. 

Some  of  the  substances  used  for  driers  are  acetate  of 
lead,  red  lead,  orange  lead,  white  lead,  chrome  yellow, 
litharge,  manganese  dioxide,  manganese  sulphate,  man- 
ganese acetate,  ferrous  sulphate,  and  ferric  oxide.  Of 

108 


DRIERS,  VARNISHES,  PAINTS  AND  STAINS  109 

late  years,  however,  the  linoleates,  resinates,  and  berates 
of  lead  and  manganese  have  come  into  common  use,  on 
account  of  the  fact  that  they  dissolve  completely  in  oil, 
so  that  no  "  foots  "  are  produced.  Also,  since  they  are 
soluble,  no  long  heating  of  the  oil  is  needed  and  paler  oils 
can  be  produced.  Some  of  these  driers  are  prepared  in 
the  following  manner: 

228.  Lead    Borate.     Dissolve    10    Ibs.   of   acetate  of 
lead  in  10  gals,  of  water  and  add  to  it  a  solution  of  6^ 
Ibs.  of  borax  in  10  gals  of  water;  wash,  filter,  and  dry. 

229.  Manganese   Borate.     Dissolve    10   Ibs.    of   man- 
ganese sulphate  in  10  gals,  of  water  and  add  to  it  a  solu- 
tion of  8  Ibs.  of  borax  in  10  gals,  of  water;   wash,  filter, 
and  dry. 

230.  Lead  Linoleate.     This  is  made  by  preparing  a 
neutral  soda  soap  from  linseed  oil  and  caustic  soda  and 
pouring  this  into  a  solution  of  lead  acetate. 

231.  Manganese  Linoleate.     Made  in  a  manner  sim- 
ilar to  the  lead  compound. 

232.  Lead  Resinate.    This  substance  is  prepared  by 
making  a  rosin  soap  and  adding  it  to  a  solution  of  lead 
acetate. 

233.  Manganese  Resinate.    Made  in  a  similar  manner, 
using  manganese  sulphate. 

234.  Linseed   Oil  Drier.    Linseed  oil   that  has  been 
strongly  boiled  with  a  large  proportion  of  drier  and  then 
mixed  with  turpentine,  forms  a  liquid  drier  which  mixes 
freely  with  paint,  and  hence  is  very  serviceable  for  the 
use  of  the  painter. 

235.  Heavy  Drier  No.  1.     Put  10  gals,  of  raw  Unseed 
oil  into  a  copper  kettle  and  heat  under  the  stack,  slowly 
adding  i  Ib.  of  borate  of  lead.    Boil  until  clear,  and, 


110      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

when  cooled  sufficiently,  slowly  add  10  gals,  of  turpentine 
and  stir  well. 

236.  Drier  No.  2.     Dissolve  as  much  lead  resinate  in 
turpentine  as  possible  and  use  only  in  the  cold.     Of  this 
drier,  5  per  cent  of  the  amount  of  oil  contained  in  the 
paint  is  used. 

237.  Japan  Drier. 

Raw  linseed  oil,  z\  gals. 

Flake  litharge,  7^  Ibs. 

Kauri  gum,  3^  Ibs. 

Granulated  manganese,  2     Ibs. 
Turpentine,  10    gals. 

Cook  the  oil,  litharge,  gum,  and  manganese  together 
until  a  drop  when  cold  is  brittle.  Then,  after  cooling  the 
mass  to  between  250°  and  300°  F.,  add  the  turpentine 
slowly. 

238.  Fine    Light    Coach    Oil.    Place    in    the    varnish 
kettle 

Raw  linseed  oil,  6|  gals. 

Borate  of  manganese,  2    oz. 
Litharge,  6    oz. 

Heat  to  375°-45o°  F.  for  several  hours,  or  until  a  sample 
placed  on  glass  becomes  solid  within  a  few  minutes. 

239.  Medium  Coach  Oil.     Following  the  above  direc- 
tions, use 

Raw  Unseed  oil,  6|  gals. 

Borate  of  manganese,  2    oz. 
Red  lead,  4    oz. 

Litharge,  6    oz. 


DRIERS,  VARNISHES,  PAINTS  AND  STAINS  111 

240.  Strong  Coach  Oil. 

Raw  linseed  oil,  6|  gal. 

Borate  of  manganese,          2    oz. 
Red  lead,  8    oz. 

Litharge  8    oz. 

Black  oxide  of  manganese,  8    oz. 

241.  Paint  and  Varnish  Remover.     In  order  to  remove 
paint  and  varnish  from  wood  or  other  material,  it  is  neces- 
sary to  treat  it  in  such  a  manner  as  to  soften  the  coating. 
When  the  coating  or  film  has  been  softened,  it  becomes  an 
easy  matter  to    remove  it  by    means    of    a    flat    putty 
knife.     There    are   many   materials    that   will    have    the 
desired  effect,  but  some  of  them  possess  marked  disad- 
vantages.    Cuastic  soda  solution,  or  a  solution  of  washing 
soda,  will  readily  soften  the  film,  but  as  they  have  a 
harmful  action  on  the  wood,  their  use  is  not  to  be  recom- 
mended.   A  most  effective  varnish  remover  may  be  made 
by  mixing  together 

Benzene,  5  parts 
Acetone,  5  parts 
Alcohol,  5  parts 

Then  melt  i  part  of  paraffine  wax  and,  while  still  liquid, 
pour  into  the  mixture.  This  preparation  is  applied  with 
a  brush,  allowed  to  stand  for  ten  minutes,  and  then  scraped 
off  with  a  knife. 

The  use  of  wax  in  varnish  remover  is  covered  by  a 
basic  patent.  This  has  resulted  in  much  litigation  on 
account  of  the  fact  that  it  is  impossible  to  make  a  satis- 
factory remover  without  the  admixture  of  some  medium 


112      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

capable  of  holding  the  solvent  in  place  until  it  has  done 
its  work. 

242.  Rust  Remover.  '  Powdered  emery  and  paraffine  oil. 

243.  Protective  Varnish  for  Iron.     Dissolve   i   Ib.   of 
paraffine  wax  in  i  gal.  of  benzine. 

244.  French  Polish.     This  polish  is  prepared  by  dis- 
solving 

Gum  copal,    4  oz. 
Gum  arabic,  3  oz. 
Gum  shellac,  i  Ib.  in 
Alcohol,          i  gal. 

245.  Spirit  Varnishes.     These  varnishes  are  made  in 
the  cold  and  are  useful  when  a  quick-drying  varnish  is 
desired. 

246.  Shellac   Varnish.     Dissolve  4   Ibs.    of   shellac   in 
i  gal.  of  alcohol. 

247.  French  Varnish.     Dissolve  5  Ibs.  of  white  shellac 
in  i  gal.  of  alcohol,  filter,  and  add  5  oz.  Venice  turpentine. 

248.  Brown  Hard  Spirit  Varnish.     Dissolve   i   Ib.   of 
sandarac,  2  Ibs.  of  orange  shellac,  4  oz.  gum  elemi,  and 
8  oz.  of  Venice  turpentine  in  i  gal.  of  alcohol. 

249.  Mastic  Varnish.     Dissolve  4^  Ibs.  of  gum  mastic 
in  i  gal.  of  turpentine. 

250.  Dammar  Varnish.     Dissolve  4  Ibs.  gum  dammar  in 
i  gal.  of  warm  turpentine. 

251.  Collodion  Varnish.     Dissolve  4  oz.  of  gun-cotton 
in  a  mixture  of  i\  qts.  of  amyl  alcohol  and  i|  qts.  of 
amyl  acetate. 

252.  Oil  Varnishes.     Oil  varnishes  are  divided  com- 
mercially  into    a  number   of   groups,   although   there   is 
very  little  difference  between  them,  either  in  the  method 


DRIERS,  VARNISHES,  PAINTS  AND  STAINS  113 

of  making  or  in  the  materials  used.  The  general  process 
in  outline  consists  of  the  following  stages:  (i)  Melting 
the  resin  or  gum  (or  "  running,"  as  it  is  known  in  the 
trade);  (2)  boiling  the  oil;  (3)  mixing  the  melted  gum 
and  boiled  oil;  (4)  boiling  the  varnish;  (5)  thinning  the 
boiled  product;  (6)  clearing. 

(1)  Running.    The  running  of  the  gum  is  carried  out 
in  copper  kettles  heated  by  direct  flame.     This  part  of 
the  process   must   have  the  utmost  care,  as  overheating 
will  give  a  poor  grade  of  varnish,  and  underheating  will 
not  give  a  uniform  product.     To  make  a  good  varnish, 
it  requires  experience  and  a  knowledge  of  just  when  to 
stop  heating. 

(2)  Oil  Boiling.     While  the  gum  is  being  "  run,"  the 
oil  to  be  used  is  boiled.     This  is  done  in  the  boiling  pot. 
The  oil  is  heated  to  about  500°  F.  for  one  to  two  hours, 
when  it  is  ready  to  mix  with  the  gum. 

(3)  Mixing.     When  the  gum  has  been  properly  melted, 
the  necessary  quantity  of  boiled  oil  is  poured  into   the 
melted  gum  with  constant  and  vigorous  stirring. 

(4)  Varnish  Boiling.     When  the  gum  and  oil  are  first 
mixed,  a  rather  cloudy  mass  is  produced,  and,  in  order  to 
make  this  transparent  and  to  make  the  varnish  string,  it 
is  necessary  to  boil  again.     The  point  at  which  to  stop 
boiling  depends  upon  the  varnish;   but  as  a  rule,  if  a  drop 
taken  between  the  thumb  and  finger  forms  strings  when 
the   fingers  are  separated,  the  end  point  is  indicated. 

(5)  Thinning.    After  the  boiling  operation  is  complete, 
the  pot  and  its  contents  are  removed  from  the  fire  and 
placed  at  some  distance  from  any  flame.     Here  it  is  mixed 
with  turpentine  to  a  working  consistency.     Although  it 
is  necessary  to  mix  the  turpentine  with  the  varnish  at  as 


114      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

high  a  temperature  as  possible,  nevertheless,  it  is  ad- 
visable to  allow  the  hot  mass  to  cool  down  somewhat 
before  adding  the  turps  (350°  F.).  The  turpentine  should 
be  introduced  in  small  quantities  at  a  time,  in  order 
that  the  mixing  may  be  properly  done  without  too  great 
a  loss  of  volatile  solvent. 

(6)  Clearing  and  Aging.  Freshly  made  varnish  is  most 
unsatisfactory  for  use,  and  all  the  best  qualities  are  sub- 
jected to  an  aging  and  clearing  process  before  they  are 
sent  out.  Thus,  on  standing,  the  more  insoluble  particles 
separate,  and  the  top  layer  becomes  clear. 

The  following  list  will  serve  to  demonstrate  the  manu- 
facture of  oil  varnishes  in  general.  The  preparation  of 
materials  and  compounding  of  varnishes  therefrom  cannot 
be  set  forth  actually  so  as  to  produce  commercial  prod- 
ucts at  all  times,  owing  to  the  variation  of  the  raw 
materials.  With  a  little  experience,  however,  the  few  form- 
ulas given  below  will  be  found  to  give  satisfactory  results. 

253.  Finishing  Body   Varnish  for   Coaches.     Melt   or 
run  8  Ibs.  of  best  African  animi,  pour  in  160  Ibs.  of  boiled 
linseed  oil,  and  boil  slowly  for  four  to  five  hours,  or  until 
it  strings  well.     Allow  to  cool  (350°  F.)  and  add  28  Ibs. 
of  turpentine. 

254.  Elastic   Carriage   Varnish.     Run   8   Ibs.    of   gum 
copal,  mix  with  20  Ibs.  of  boiled  linseed  oil,  add  2\  oz.  of 
dried  copperas  and  2\  oz.  of  litharge,  boil  until  it  strings, 
cool,  and  thin  with  44  Ibs.  of  turpentine. 

255.  Extra  Fine  Copal  Varnish. 

African  copal,  15  Ibs. 

Fine  light  coach  oil  (hot),  30  Ibs. 

thin  with        Turpentine,  48  Ibs. 


DRIERS,  VARNISHES,   PAINTS  AND  STAINS  115 

256.  Elastic  Varnish. 

African  copal,  5  Ibs. 

Animi  gum,  5  Ibs. 

Medium  coach  oil  (hot),  30  Ibs. 

thin  with        Turpentine,  48  Ibs. 

257.  Tool  Varnish. 

Gum  kauri,  15  Ibs. 

Rosin  W  G,  15  Ibs. 

Strong  coach  oil  (hot),  12  Ibs. 

thin  with        Turpentine,  29  Ibs. 

Benzine,  24  Ibs. 

258.  Waterproof  Varnish.     Within  the  past  few  years 
Chinese  Wood  Oil  has  come  into  extensive  use  in  the 
preparation  of  varnishes  for  the  reason  that  it  can  be 
used  in  conjunction  with  ordinary  rosin.     The  oil  is  heated 
to  about  400°  F.  in  the  presence  of  rosin  and  then  thinned 
with    turpentine.     A    great    difficulty   is    encountered    in 
making   this  varnish  on  account  of  the  tendency  of  the 
oil  to  polymerize  or  become  solid.     When  this  happens, 
the  batch  is  worthless. 

259.  Lithographic    Varnish.     In   making    this    varnish 
a  great  deal  depends  upon  the  time  of  treatment  and  the 
temperature  attained.     The  longer  the  treatment  and  the 
higher  the  temperature,  the  thicker  will  be  the  resulting 
product. 

In  making  a  standard  varnish,  place  the  linseed  oil 
in  a  copper  kettle  and  slowly  raise  the  temperature  to 
550°  F.,  holding  it  at  this  point  for  about  one  hour.  Now 
lower  the  heat  and  allow  the  varnish  gradually  to  cool. 
The  result  should  be  a  fairly  heavy-bodied  product. 


116      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

260.  Ready-mixed  Paint.  There  is  hardly  an  industry 
which  has  made  more  rapid  progress  in  the  past  fifteen 
years  than  the  manufacture  of  "  ready  to  use  "  paints. 
Nearly  every  user  of  paint  goes  through  the  stage  of 
desiring  to  become  his  own  paint  manufacturer,  and  there 


FIG.  29. 

are,  even  at  present,  many  who  fondly  imagine  that  they 
can  prepare,  by  means  of  a  wooden  paddle  and  a  wash- 
tub,  mixed  paints  capable  of  ranking  as  protective  and 
decorative  agents  with  that  material  compounded  by  the 
aid  of  powerful  and  special  machinery. 

There    has   been   much    dissatisfaction   in   regard    to 


DRIERS,  VARNISHES,  PAINTS  AND  STAINS 


117 


ready-mixed  paints,  and  justly,  as  numerous  brands  have 
been  placed  upon  the  market  that  are  not  much  better 
than  chalk  and  water.  Conscientious  manufacturers,  how- 
ever, have  done  much  to  bring  these  frauds  to  light; 
and  we  may  look  to  a  time  in  the  not  far  distant  future 
when  all  brands  of  paint  will  be  properly  labeled  and 
the  public  educated  to  the  requirements  of  a  ready-to-use 
paint.  In  fact,  many  states  already  have  pure  paint  laws. 

261.  In   the   manufacture   of  ready-mixed  paint,   the 
necessary  amount  of  raw 

linseed  oil  is  placed  in  the 
mixing  machine,  Fig.  29. 
The  body  containing  the 
coloring  matter  is  intro- 
duced in  small  portions 
at  a  time,  new  lots  being 
added  only  as  the  paste 
becomes  limpid.  The 
mixture  is  then  run 
through  the  mill,  Fig.  30, 
until  perfectly  smooth 
when  rubbed  out  on  glass. 
It  is  then  thinned  as 
desired. 

The  method  'of  pro- 
cedure   varies    to    quite    an    extent   in    different  plants, 
although  all  are  based  on  the  same  general  principle. 

From  the  following  formulas  the  general  method  may 
be  noted,  and  various  shades  produced. 

262.  White.     Pour   into    the   can   of   the  mixer    n.6 
Ibs.  of  raw  linseed  oil  and  set  the  machine  in  motion. 
Now  add  slowly  a  mixture  of 


FIG.  30. 


118       LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

Dry  white  lead,  25  Ibs. 

Zinc  oxide,  25  Ibs. 

Mix  thoroughly,  or  until  a  smooth  paste  is  obtained 
which  will  run  easily  from  the  can.  This  paste  is  passed 
through  the  mill,  the  stone  being  so  adjusted  as  to  secure 
a  product  free  from  lumps  when  rubbed  out  on  glass. 
After  passing  through  the  mill,  it  is  brought  into  the 
mixer  again  and  thinned  by  adding 

Raw  linseed  oil,  15     Ibs. 

Boiled  linseed  oil,  10     Ibs. 

Japan  drier,  3.5  Ibs. 

Turpentine,  1.5  Ibs. 

When  thoroughly  mixed  it  is  run  into  cans  and  is  ready 
for  use. 

A  quantity  of  the  above  thinning  mixture  should  be 
made  up,  kept  in  stock,  and  labeled  Standard  Oil,  to  be 
subsequently  referred  to  as  such.  The  following  formulas 
should  be  worked  out  in  the  same  manner  as  just  given  for 
white,  taking  the  precaution  to  have  the  mill  thoroughly 
cleaned  from  one  color  before  introducing  another.  A 
good  plan  also  is  to  run  from  light  to  darker  shades,  thus 
obviating  the  necessity  of  so  much  cleaning  of  the  mill 
and  mixer.  Where  facilities  will  permit,  it  is  advisable 
to  use  one  mixer  and  mill  for  each  color  manufactured. 

263.  Outside  White. 

Linseed  oil,  nj  Ibs. 

White  lead,  21    Ibs. 

Zinx  oxide,  18    Ibs. 

Whiting,  4±  Ibs. 

Barytes,  3    Ibs. 


DRIERS,  VARNISHES,  PAINTS  AND  STAINS  119 


[i  with        Linseed  oil,  (raw) 

15    Ibs. 

Turpentine, 

if  Ibs. 

Japan  drier, 

Jib. 

264. 

Light  Colonial. 

Dry  white  lead, 

25     Ibs. 

Zinc  oxide, 

25     Ibs. 

Lemon  chrome  yellow, 

i     Ib. 

Raw  linseed  oil, 

12     Ibs. 

a  with        Standard  oil 

27     Ibs. 

265.  Cream. 

White  lead,  25     Ibs. 

Zinc  oxide,  25     Ibs. 
Lemon  chrome  yellow,      .6  Ib. 
Medium  chrome  yellow,     .3  Ib. 

Raw  Unseed  oil,  11.5  Ibs. 

thin  with        Standard  oil,  26.5  Ibs. 

266.  Yellow. 

White  lead,  20     Ibs. 

Zinc  oxide,  20     Ibs. 

Chrome  yellow,  i     Ib. 

Raw  linseed  oil,  11.5  Ibs. 

thin  with        Standard  oil,  26.0  Ibs. 

267.  Straw. 

White  lead,  20     Ibs. 

Zinc  oxide,  20    Ibs. 

Golden  ocher,  18     Ibs. 

Orange  yellow,  i     Ib. 

Raw  linseed  oil,  14     Ibs. 

thin  with        Standard  oil,  28.5  Ibs. 


120      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

268.  Flesh. 

White  lead,  20     Ibs. 

Zinc  oxide,  20     Ibs. 

Golden  ocher,  5     Ibs. 

French  ocher,  2.9  Ibs. 

Princess  metallic,  .3  Ib. 

Lamp-black,  .1  Ib. 

Raw  linseed  oil,  11.5  Ibs. 

thin  with        Standard  oil  26     Ibs. 

269.  Light  Blue. 

White  lead,  22.5  Ibs. 

Zinc  oxide,  22.5  Ibs. 

Chinese  blue,  5.0  Ibs. 

Raw  linseed  oil,  11.5  Ibs. 

thin  with        Standard  oil,  30.0  Ibs. 

270.  Dark  Blue. 

White  lead,  20     Ibs, 

Zinc  oxide,  20    Ibs. 

Prussian  blue,  10     Ibs. 

Raw  linseed  oil,  11.5  Ibs. 

thin  with        Standard  oil,  30.0  Ibs. 

271.  Azure  Blue. 

White  lead,  25    Ibs. 

Zinc  oxide,  25     Ibs. 

Chinese  blue,  .1  Ib. 
Lemon  chrome  yellow,      .3  Ib. 

thin  with        Standard  oil,  26.0  Ibs. 


DRIERS,  VARNISHES,  PAINTS  AND   STAINS  121 

272.  Drab. 

White  lead,  24.5  Ibs. 

Zin  oxide,  24.5  Ibs. 

Lamp-black,  .2  Ib. 

Raw  linseed  oil,  11.5  Ibs. 

thin  with        Standard  oil,  30.0  Ibs. 

273.  Slate. 

White  lead,  22.5  Ibs. 

Zinc  oxide,  22.5  Ibs. 

Lamp-black,  2.0  Ibs. 

Raw  linseed  oil,  11.5  Ibs. 

thin  with        Standard  oil,  30.0  Ibs. 

274.  Cement  Paint  (Drab). 

Linseed  oil,  30     Ibs. 

White  lead,  25     Ibs. 

Sub.  white  lead,  25     Ibs. 

Zinc  oxide,  35     Ibs. 

Barytes,  15     Ibs. 

Drop  black  2.5  Ibs. 

Chrome  yellow,  1.2  Ibs. 

thin  with        Linseed  oil,  35.0  Ibs. 

Turpentine,  8.0  Ibs. 

Japan  drier,  4.0  tbs. 

275.  Machine  Gray. 

Linseed  oil,  n     Ibs. 

White  lead,  20     Ibs. 

Zinc  oxide,  20     Ibs. 

Graphite,  i     Ib. 

Lamp-black,  .5  Ib. 

Chinese  blue,  .2  Ib. 


122      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 


thin  with 

Linseed  oil, 

15     Ibs. 

Japan  drier, 

2     Ibs. 

Turpentine, 

i     Ib. 

276.  Dark  Lead. 

White  lead, 

21.2  Ibs. 

Zinc  oxide, 

21.2  Ibs. 

Golden  ocher, 

6.5  Ibs. 

Chinese  blue, 

.1  Ib. 

Graphite, 

1.2  Ib. 

Raw  linseed  oil, 

ii     Ibs. 

thin  with 

Standard  oil, 

24     Ibs. 

277.  Apple  Green. 

White  lead, 

22.5  Ibs. 

Zinc  oxide, 

22.5  Ibs. 

Lemon  chrome  yellow, 

5.5  Ibs. 

Chrome  green, 

24.0  Ibs. 

Raw  linseed  oil, 

13.5  Ibs. 

thin  with 

Standard  oil, 

22.5  Ibs. 

278.  Sage  Green. 

White  lead, 

20     Ibs. 

Zinc  oxide, 

20     Ibs. 

French  ocher, 

13     Ibs. 

Chrome  green, 

5.8  Ibs. 

Lamp-black, 

1.8  Ibs. 

Venetian  red, 

•3lb. 

Raw  linseed  oil, 

12     Ibs. 

thin  with 

Standard  oil, 

28     Ibs. 

DRIERS,  VARNISHES,  PAINTS  AND  STAINS  123 

279.  Dark  Olive  Green. 

Golden  ocher,  35     Ibs. 

French  ocher,  6     Ibs. 

Drop  black,  9.8  Ibs. 

Chrome  green,  1.2  Ibs. 
Lemon  chrome  yellow,       .2  Ib. 

Raw  linseed  oil,  13.5  Ibs. 

thin  with        Standard  oil,  34.5  Ibs. 

280.  Brunswick  Green. 

Extra  deep  Brunswick 

green,  40     Ibs. 

Lemon  chrome  yellow,     1.6  Ibs. 

Linseed  oil,  11.5  Ibs. 

thin  with        Standard  oil  28.5  bis. 

281.  Outside  Green. 

Linseed  oil,  25  Ibs. 

Yellow  ocher,  38  Ibs. 

Lamp-black,  2  Ibs. 

Chrome  green,  8.2  Ibs. 

thin  with        Standard  oil,  56  Ibs. 

Kauri  varnish,  8  Ibs. 

Japan  drier,  8  Ibs. 

282.  Indian  Red. 

Venetian  red,  66.2  Ibs. 

Princess  metallic,  12.3  Ibs. 

Raw  linseed  oil,  24     Ibs. 

thin  with        Standard  oil,  54.3  Ibs. 

By  changing  the  proportion  of  pigment,  any  range  of 
shade  and  tint  may  be  obtained.  The  above  are  merely 
given,  therefore,  to  illustrate  the  method  of  procedure. 


124      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

283.  Putty.     This    substance    is    very    important,    for 
setting  glass,    filling  nail   holes,  etc.      It   is   made   on  a 
commercial    scale    by  mixing    the   constituents    together 
under  a  heavy  stone  roller  running  in  a  steel  foundation. 
The  process  of  manufacture  may,   however,   be   demon- 
strated in  the  laboratory  by  means  of  a  kneading  machine 
and  is  carried  out  as  follows: 

Three  Ibs.  of  raw  linseed  oil  is  placed  in  the  machine. 
A  mixture  of  n  Ibs.  of  whiting  and  5  Ibs.  of  lead  car- 
bonate is  slowly  added  to  the  oil,  the  arms  being  kept  in 
constant  motion.  Care  must  be  taken  to  have  the  oil 
and  mixture  smooth  before  introducing  new  portions. 
The  finished  product  should  not  stick  to  the  hands,  but, 
if  such  is  the  case,  a  small  amount  of  the  mixture  in  excess 
of  the  above  may  be  added.  The  putty  is  then  allowed  to 
stand  several  days  to  sweat,  when  it  is  again  kneaded  with 
the  addition,  if  necessary,  of  a  small  amount  of  whiting. 

284.  Oil  Stains  and  Wood  Fillers.     The  following  list 
of  formulas  will  serve  to  illustrate  the  large  class  of  sub- 
stances put  on  the  market  as  wood  fillers  and  oil  stains. 
They  consist  of  a  base  to  which  various  pigments  may 
be  added   according   to   the  effect  desired.     The  mixing 
and  grinding  are  conducted  as  given  under  ready-mixed 
paints. 

285.  Stain  and  Filler  Base.     Twelve  Ibs.  of  starch  is 
placed  in  the  mixer  and  worked  into  a  thin  paste  with 
3    Ibs.    of   water.     When   thoroughly   triturated,    27   Ibs. 
boiled  linseed  oil,  13  Ibs.  turpentine,  and  38  Ibs.  of  japan 
are  added,  the  whole  being  run  until  perfectly  smooth. 
This  should  be  made  in  large  amounts,   ready  for  use, 
and  labeled  "  Stain  Base."    It  is  then  used  as  a  body 
for  the  various  stains. 


DRIERS,  VARNISHES,  PAINTS  AND  STAINS  125 

286.  Light  Oak  or  Ash  Stain.     Place  in  the  mixing 
machine  7  Ibs.  of  boiled  oil  and  3^  Ibs.  turpentine.     To 
this  slowly  add  a  mixture  of  i\  Ibs.  raw  sienna,  12  oz. 
burnt  umber,  and  4  Ibs.  silica.     When  thoroughly  incor- 
porated, transfer  to  mill,  grinding  until  perfectly  smooth 
when  rubbed  out  on  glass.     Return  to  mixer  and  thin 
with  72  Ibs.  of  stain  base.     Work  well  and  can  while  still 
in  suspension. 

Prepare  the  following  oil  stains  according  to  the  gen- 
eral directions  given  for  light  oak  or  ash: 

287.  Dark  Oak  Stain. 

Silica  3.2  Ibs. 

Burnt  Italian  sienna,  3.2  Ibs. 

Burnt  umber,  1.6  Ibs. 

Boiled  linseed  oil,  7.2  Ibs. 

Turpentine,  3.6  Ibs. 

Stain  base,  72     Ibs. 

288.  Chestnut  Stain. 

Silica,  6.4  Ibs. 

Burnt  Italian  sienna,  1.6  Ibs. 

Boiled  Turkey  umber,  .8  Ib. 

Boiled  linseed  oil,  7.2  Ibs. 

Turpentine,  3.6  Ibs. 

Stain  base,  72     Ibs. 

289.  Yellow  Pine  or  Maple  Stain. 

Raw  Italian  sienna,          1.6  Ibs. 
Chrome  yellow,  1.2  Ibs. 

Silica,  5.8  Ibs. 


126       LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

Boiled  linseed  oil,  7.2  Ibs. 

Turpentine,  3.6  Ibs. 

Stain  base,  72     Ibs. 

290.  Walnut  Stain. 

Burnt  Turkey  umber,  9.2  Ibs. 

Burnt  Italian  sienna,  1.2  Ibs. 

Boiled  linseed  oil,  7.2  Ibs. 

Turpentine,  3.6  Ibs. 

Stain  base,  90     Ibs. 

291.  Mahogany  Stain. 

Burnt  Italina  sienna,  10     Ibs. 

Burnt  Turkey  umber,  1.6  Ibs. 

Boiled  linseed  oil,  7.2  Ibs. 

Stain  base,  90     Ibs. 


FIG.  31. 

Oil  stains  are  often  made  from  coal-tar  colors  soluble 
in  oil. 

Water  stains  are  prepared  by  dissolving  various  coal- 
tar  colors  in  water. 


DRIERS,  VARNISHES,  PAINTS  AND  STAINS  127 

Spirit-soluble  stains  are  made  by  dissolving  the  color 
base  in  alcohol  or  a  good  spirit  varnish. 

Oil  varnish  stains  may  be  made  by  substituting  a  good 
grade  of  oil  varnish  for  the  linseed  oil  in  the  above  for- 
mula; or  they  may  be  made  by  dissolving  oil-soluble, 
coal-tar  colors  in  varnish. 

292.  Enamels.  These  protective  coatings  are  made  by 
grinding  the  pigment  in  varnish.  The  process,  however, 
cannot  be  carried  out  in  a  buhr  stone  mill,  as  is  the  case 
with  paint ;  it  must  be  done  in  a  roller  mill.  A  mill  of  this 
type  is  shown  in  Fig.  31. 


CHAPTER  VII 
SOAP  AND  ALLIED   PRODUCTS 

293.  Soap.     In    the   manufacture    of    soap    there    are 
three  general  processes,   namely,   cold-made  soaps,   half- 
boiled   soaps,   and   boiled  soaps.     The  three   classes   will 
be  taken  up  in  order. 

The  installation  of  a  miniature  soap  works  requires 
provision -for  a  lye  tank,  kettle,  crutcher,  frames,  slabber, 
cutting  machine,  chipper,  mill,  plodder,  press,  and  dies, 
all  of  which  may  be  secured  from  manufacturers  of  soap 
machinery.  ,  Some  of  the  following  formulas  can  also  be 
worked  out  on  a  small  scale  by  using  a  good-sized  iron 
kettle,  a  small  garden  rake  with  a  wooden  box  to  serve 
as  a  frame,  and  a  piece  of  piano  wire  or  thin  knife  to 
cut  the  cake. 

The  proportions  given  hereafter  are  for  a  crutcher 
having  a  capacity  of  100  Ibs.,  but  they  may  be  varied  to 
suit  the  requirements. 

294.  Cold-made  Soap.     The  term  "  cold-made  "  soap 
is  applied  to  those  soaps  in  which  the  fat  and  oil  are  heated 
only  sufficiently   to  melt   them   (not  over   120°   F.)  and 
the    cold    lye    then    introduced.     This    process    gives    a 
hard  soap,  but  is  quite  apt  to  contain  either  unsaponified 
fats  or  free  alkali. 

In  making  soap  by  the  cold  process,  care  must  be  taken 
to  have  all  the  materials  perfectly  fresh  and  clean.  The 

128 


SOAP  AND  ALLIED  PRODUCTS 


129 


lyes  should  never  be  used  the  same  day  they  are  made. 
Use  the  lye  cold. 

Process.  Weigh  out  34  Ibs.  of  tallow  and  place  in 
the  crutcher,  Fig.  32,  turn 
on  the. dry  steam,  and  heat 
until  melted.  When  all  of 
the  tallow  is  in  a  liquid 
state,  introduce  17  Ibs.  of 
cocoanut  oil,  17  Ibs.  of 
cotton-seed  oil,  and  agi- 
tate. Secure  a  temperature 
of  between  115°- 120°  F., 
and  then  add  35  Ibs.  of  36° 
Be.  caustic  soda  lye.  The 
mass  is  then  crutched 
(stirred)  until  the  soap 
begins  to  set,  indicated  by 
the  formation  of  flakes 


FIG.  32. 


when  a  sample  .s  taken  upon  the  paddle.  It  is  next  run  into  a 
frame,  Fig.  33,  and  allowed  to  stand  for  twenty-four  hours 

to  complete  saponification  and 
harden.  The  sides  and  ends  of 
the  frame  are  then  removed, 
and  the  cakes  passed  through 
the  slabber  and  cutting  machine, 
Figs.  34  and  35.  The  bars  of 
soap  thus  formed  are  placed  on 
racks  in  the  drying  room  and 
allowed  to  stand  for  several 
days  until  thoroughly  dry.  The 

bars  are  now  run  through  the  chipper,  Fig.  36,  where  they 
are  cut  into  flakes  about  one-sixteenth  of  an  inch  thick. 


FIG.  33. 


130      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

These   chips   are   spread   on  wire  racks   and  returned  to 
the   drying   room.    When  the  chips  are  brittle  and  snap, 


FIG.  34. 


FIG.  35. 


they    are   ready  for    the    milling    process,   conducted    as 
follows: 


SOAP  AND  ALLIED  PRODUCTS 


131 


Milling.    The  chips  are  run  through  the  granite  roller 
mill,  Fig.  37,  and  collected  in  a  box  sufficiently  large  to 


FIG.  36. 


FIG.  37. 


FIG.  38. 

hold  the  entire  batch.     Eight  ozs.  of  a  good  soap  perfume 
(Oil    of    Rose    Geranium)    is    then    sprinkled    over    the 


132      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 


chips,  which  are  shaken  up  uniformly,  to  distribute  the  oil, 
and  then  run  again  through  the  mill,  the  granite  rollers 
being  a  little  closer  this  time,  and  finally  set  tight.  Repeat 
the  milling  several  times,  or  until  a  uniform  ribbon  of 
about  the  thickness  of  paper  comes  from  the  knife. 

.  Plodding.  From  the  mill  the  soap  is  passed  to  the 
plodder,  Fig.  38,  a  machine  provided  with  a  screw  com- 
pressor. The  nose  of  the 
plodder  is  slightly  warmed  and 
the  milled  soap  introduced. 
As  soon  as  the  soap  begins  to 
discharge,  the  forming  plate  is 
adjusted.  Keep  the  hopper  of 
the  plodder  filled,  as  this  will, 
in  a  measure,  keep  out  air 
bubbles  and  prevent  the  soap 
from  being  streaked. 

The  first  15  or  20  feet 
should  be  returned  to  the  mill, 
as  the  bars  have  not  received 
the  full  pressure.  As  soon  as 
the  soap  runs  smooth  and  free 
from  streaks,  it  may  be  cut 
into  any  convenient  length  and 
pressed. 

Pressing.  The  dies  being 
adjusted  and  the  press,  Fig.  39,  well  oiled,  the  faces  are 
then  moistened  with  a  strong  salt  solution  and  the  cake 
placed  in  position.  Next,  a  heavy  blow  is  dealt  with  the 
foot,  followed  by  a  second  short  blow  as  the  original  stroke 
rebounds.  After  the  first  10  or  12  cakes  have  been  pressed, 
it  will  not  be  necessary  to  moisten  the  die  so  frequently. 


FIG.  39. 


SOAP  AND  ALLIED  PRODUCTS  133 

295.  Green  Castile  Soap. 

Tallow,  25  Ibs. 

Cocoanut  oil,  12  Ibs. 

Olive  oil  foots  (green),  25  Ibs. 
Cotton-seed  oil,  9  Ibs. 

Soda  lye  at  35°  Be.,      36  Ibs. 

Warm  the  fats  and  oils  to  110°  F.,  crutch  in  the  lye,  and, 
when  the  soap  has  formed,  run  into  frames,  allow  to 
harden,  and  then  follow  the  general  directions. 

296.  Laundry  Soap. 

Tallow,  30  Ibs. 

Cocoanut  oil,  30  Ibs. 

Caustic  soda  lye,  36°  Be.,  30  Ibs. 

Sodium  carbonate  solution,  35°  Be.,    8  Ibs. 
Oil  of  mirbane,  8  ozs. 

This  soap  is  cut  into  cakes  and  dried,  but  is  not  milled  as 
in  the  case  of  toilet  soaps. 

297.  Half-boiled    Soaps.     By    this   process   very   fine 
soap  can  be  made,  almost  equal  to  the  best  boiled  soap. 
But  with  them,  the  same  as  with  cold-process,  great  care 
must  be  taken  to  have  perfectly  pure  stock. 

298.  Palm  Oil  Soap.    Place  in  the  crutcher 

Palm  oil,  1 8  Ibs. 
Cocoanut  oil,  36  Ibs. 
Tallow,  9  Ibs. 

and  heat  to  a  temperature  of  150°  F. 

Add  36  Ibs.  of  35°  Be.  soda  lye  and  crutch  slowly  for 
about  three  minutes;  now  cover  up  to  keep  warm,  and 
allow  to  stand  for  if  hours.  At  the  end  of  this  time  the 


134      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

charge  will  have  wanned  up  to  I7o°-i8o°  F.  The  crutcher 
is  then  started  very  slowly.  At  first,  the  soap  will  be 
thick  and  hard  to  crutch,  but  will  soon  thin  down  and 
become  hotter.  If,  after  crutching  for  ten  minutes,  the 
soap  for  some  reason  does  not  thin  down  and  get  hot, 
turn  on  a  little  steam,  being  careful  not  to  raise  the 
temperature  over  180°  F.  After  the  soap  has  been  well 
crutched  and  is  free  from  lumps,  it  should  be  tested  by 
rubbing  some  in  the  palm  of  the  hand;  if  saponification 
is  complete,  it  will  form  flakes,  whereas  if  insufficient  alkali 
is  present,  it  will  remain  like  a  fat.  Also  test  for  strength 
on  the  tip  of  the  tongue.  The  soap  should  taste  a  little 
sharp;  if  too  mild,  add  a  small  amount  of  lye  until  the 
latter  can  just  barely  be  tasted.  If,  on  the  other  hand, 
it  at  first  burns  the  tongue,  add  a  little  more  cocoanut  oil. 

After  the  addition  of  alkali  or  fat,  crutch  well  and, 
when  it  begins  to  thicken  (shown  by  the  soap  dropping 
free  from  the  paddle  in  flakes),  run  into  the  frame  imme- 
diately and  allow  to  cool. 

For  laundry  soap,  the  perfume  is  crutched  in  just  before 
framing,  whereas,  for  toilet  soap,  it  is  added  only  at  the 
time  of  milling.  Eight  ozs.  of  citronella  oil  or  other 
essential  oil  will  perfume  100  Ibs.  of  soap. 

299.  Green  Castile  Soap. 

Tallow,  28  Ibs. 

Olive  oil  foots  (green),       28  Ibs. 
Cocoanut  oil,  14  Ibs. 

Mix  the  foregoing  and  warm  to  150°  F.,  then  add  a  mix- 
ture of 

Caustic  soda  lye,      33°  Be.,  36  Ibs. 

Caustic  potash  lye,  35°  Be.,    4  Ibs. 


SOAP  AND  ALLIED  PRODUCTS  135 

300.  Tar  Soap. 

Cocoanut  oil,  25  Ibs. 

Olive  oil  foots,  25  Ibs. 

Caustic  soda-lye  at  35°  Be.,  30  Ibs. 
Pine  tar,  5  Ibs. 

Glycerine,  5  Ibs. 

Warm  the  oils,  tar,  and  glycerine  together.  When  at 
150°  F.,  crutch  in  the  lye  and  continue  crutching  until 
all  are  well  combined;  cover  up  and  allow  to  stand  one 
and  one-half  to  two  hours.  Then  follow  general  directions. 

301.  Laundry  Soap 

Tallow,  31  Ibs. 

Cocoanut  oil,  6  Ibs. 

Rosin  W  G,  19  Ibs. 

Caustic  soda  lye  at  33°  Be.,  32  Ibs. 

Melt  the  tallow  and  cocoanut  oil,  then  introduce  19  Ibs. 
of  rosin;  when  melted  well  together,  allow  to  cool  down  to 
130°  F.,  then  add  the  lye,  letting  the  soap  stand  for  one  and 
one-half  to  two  hours.  When  the  soap  is  finished,  and  just 
before  framing,  add  8  Ibs.  of  sodium  carbonate  solution, 
35°  Be.,  and  8  ozs.  of  citronella.  Crutch  well  and  frame. 
When  the  soap  has  set  sufficiently  long  to  harden  properly, 
it  is  cut  into  cakes  and,  as  soon  as  dry,  is  ready  for  use. 

302.  Dog  Soap 

Tallow,  50    Ibs. 

Cocoanut  oil,  5    Ibs. 

Caustic  soda  lye  at  36°  Be.,  27^  Ibs. 
Strong  tobacco  solution,  5  Ibs. 
Powdered  sulphur,  5  Ibs. 

Carbolic  acid,  5    ozs. 


136      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 


The  tobacco  solution  is  made  by  boiling  tobacco  stems  in 
water.  Mix  the  sulphur  and  the  tobacco  solution  together. 
When  the  soap  is  well  formed,  crutch  in  the  warm  sul- 
phur and  tobacco;  then  add  the  carbolic  acid  and 
frame. 

303.  Boiled  Soaps.  Owing  to  the  recovery  of  gly- 
cerine, this  process  is  em- 
ployed very  largely;  and  in 
fact  the  bulk  of  soap  is 
manufactured  in  this  manner. 
To  illustrate  the  process,  we 
will  take,  as  an  example,  the 
manufacture  of  palm  oil  soap. 
304.  Palm  Oil  Soap. 

Tallow,  100  Ibs. 
Rosin,  100  Ibs. 
Palm  oil,  10  Ibs. 

Put  the  tallow  into  the  kettle 
(Fig.  40)  and  begin  boiling 
with  open  steam,  adding  caus- 
tic soda  lye  at  10°  Be.  (about 
90  Ibs.) ;  continue  boiling  until 
the  alkali  strength  is  all 
absorbed.  Now,  boiling  con- 


FIG.  40. 


stantly  add  stronger  lye  (about  100  Ibs.),  at  15°  Be.,  until 
the  strength  is  all  absorbed.  Continue  the  boiling,  but 
add  stronger  lye  at  about  20°  Be.  until  the  soap  is  strong 
and  ready  to  grain.  Boil  well,  adding  enough  dry  salt  to 
cause  the  lye  to  separate  and  run  free  from  the  soap. 
Close  off  the  steam  and  allow  the  lye  to  settle. 

Rosining,     Run  off  the  spent  lye  and  add  about  160 


SOAP  AND  ALLIED  PRODUCTS  137 

Ibs.  of  lye  at  15°  Be.,  boiling  well  with  the  open  steam 
until  the  soap  becomes  firm  and  of  good  grain.  While 
the  soap  is  boiling  spread  the  broken  rosin  over  the 
surface,  and,  as  the  alkali  strength  is  absorbed,  add 
lye  at  15°  Be.  When  nearly  all  of  the  rosin  has  been 
put  in,  add  salt  to  keep  the  soap  open,  and  float  the  rosin 
on  salt  strength  instead  of  the  alkali  strength.  After  all 
of  the  rosin  has  been  introduced,  boil  well  with  closed 
steam  for  three  or  four  hours  until  the  curd  is  round  and 
dry;  allow  the  soap  to  settle  overnight. 

Strengthening.  Run  away  the  spent  lye  for  glycerine 
recovery.  Begin  boiling  with  the  open  steam,  running 
in  about  80  Ibs.  of  lye  at  10°  Be.;  boil  well  until  the  soap 
becomes  thin.  Then,  while  boiling,  add  lye  at  20°  Be. 
until  the  soap  opens  and  is  sharp  with  alkali.  Continue 
the  boiling  for  about  five  hours  with  the  closed  steam 
only,  after  which  the  soap  should  have  a  hard,  strong  grain 
and  be  rough  on  the  surface.  Shut  off  the  steam  and 
allow  to  settle  overnight. 

305.  Finishing.     Run  off  and  save  the  lye  that  has 
settled  out,  as  it  contains  alkali  strength  which  can  be 
used  again.     Turn  on  the  open  steam  and  add  the  10 
Ibs.  of  palm  oil,  running  in  a  little  water  to  thin  the  soap. 
If  the  soap  is  weak,  add  lye  at  5°  Be.     When  the  soap 
is  finished,  it  should  be  smooth  and  shining,  should  boil 
with  a  rolling  motion;  and  a  sample  taken  on  the  trowel 
should  slide  off  in  flakes. 

306.  Framing.    Allow  the  soap  to  settle  a  few  days 
until    it   has    cooled   to   about   145°   F.      Run  into   the 
crutcher  enough  for  one  frame  and  add  6  to  8  per  cent  of 
soda  ash  solution  at  36°  Be.     Crutch  well  for  two  minutes, 
add  the  perfume,  and  crutch  until  smooth.     Dump  into 


138      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

the  frame  and  stand  several  days  to  harden.  On  setting, 
it  is  slabbed  and  cut,  but  not  milled  as  in  the  case  of 
toilet  soap. 

307.  Rosin  'Soap.     Inasmuch  as  plain  tallow  soap  does 
not  lather,  it  is  always  necessary  to  add  something  to  make 
it  do  so.     In  laundry  soap,  rosin  is  used.     For  a  cheaper 
and   harder  product,  silicate  of   soda  is   sometimes    em- 
ployed.    The  following  formula  will  serve  to  illustrate  a 
soap  of  this  character: 

Tallow,  150  Ibs. 

Rosin,  75  Ibs. 

Sodium  silicate,     15  Ibs. 

The  method  of  manufacture  is  the  same  in  this  case  as 
for  the  previous  example.  After  finishing,  however,  the 
silicate  of  soda  is  added  as  follows: 

Put  the  silicate  of  soda  into  a  small  kettle  and  add 
water,  boiling  until  it  registers  5°  Be.  (hot);  then  add 
soda  ash  until  it  registers  7°  Be.,  then  salt  until  it  makes 
8°  Be.,  while  boiling  hot.  Now  run  about  70  Ibs.  of  the 
soap  into  the  crutcher  and  add  30  Ibs.  of  the  hot  silicate 
of  soda  solution.  Crutch  well,  add  the  perfume,  and 
continue  crutching  until  the  soap  starts  to  form.  Dump 
into  the  frame  and  treat  as  directed  above. 

308.  Soft  Soap.     "  Transparent  "  soft  soap  is  in  good 
demand  under  the  name  of  "glycerine  soft  soap"    " crown 
soap,"  etc.     Its  chief  consitutent  is  linseed  oil,  and  the 
lye  most  suitable  is  that  from  caustic  potash.     The  lye 
is  prepared  several  days  before  using  in  order   that  it 
may  become  clear.     A  very  good  soap  can  be  made  by 
melting  4  Ibs.  of  rosin  in  a  crutcher  or  iron  kettle  and 


SOAP  AND  ALLIED  PRODUCTS  139 

adding  21  Ibs.  of  linseed  oil  and  21  Ibs.  of  cotton-seed 
oil.  The  temperature  is  raised  to  160°  F.,  and  a  mix- 
ture of  42  Ibs.  of  caustic  potash  lye,  22°  Be.,  and  12  Ibs.  of 
caustic  soda  lye,  25°  Be.,  introduced.  The  mass  is  then 
crutched  for  five  minutes,  allowed  to  stand  for  two  hours, 
and  crutched  again  until  the  soap  is  smooth.  It  is 
finally  run  into  the  container,  and,  when  cool,  is  ready  for 
use. 

309.  Liquid   Soap.     Heat  40  Ibs.   of  cocoanut  oil   to 
220°  F.     Introduce  50  Ibs.  of  22°  Be.  caustic  soda  solution, 
crutch  well  for  five  minutes,  or  until  smooth,  and  add  a 
mixture  of  5  Ibs.  of  alcohol  and  5  Ibs.  of  glycerine.     Crutch 
again  for  five  minutes  and  let  stand  two  hours.     Again 
crutch  until  smooth.     This  soap,  when  cool,  will  set  to 
a  stiff  paste.    It  is  used  as  a  base  for  making  liquid  soaps, 
by  dissolving  6  ozs.  in  i  qt.  of  boiling  water  and  adding, 
when  cool,  2  ozs.  of  alcohol. 

310.  Sand  Soap  Paste.     Prepare  a  base  soap  as  under 
Liquid  Soap,   but  without   the   addition  of  alcohol  and 
glycerine.     After   standing   for    two   hours,   it   is   mixed 
with    50  Ibs.   of  sea-sand,  crutched  well,  and    run   into 
frames. 

311.  Soap  Powder.     There  are  many  kinds  of  soap 
powders  on  the  market.     They  are  all,  however,  prepared 
from  soap  and  soda  ash;    sometimes  borax  is  also  used. 
The  following  will  serve  as  an  illustration: 

Eight  Ibs.  of  tallow  and  8  Ibs.  of  cocoanut  oil  are 
placed  in  the  crutcher  and  heated  to  I5o°-i6o°  F.;  8 
Ibs.  of  caustic  lye,  33°  Be.,  is  now  crutched  in  and  the  soap 
allowed  to  stand  for  two  hours.  At  the  end  of  this  time, 
crutch  until  thin  and  add  hot  water  until  quite  thin. 
Crutch  in  \  pound  of  sulphate  of  soda,  dissolved  in  hot 


140      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

water,  and  then  add  25  Ibs.  of  soda  ash,  keeping  the  soap 
thin  by  the  addition  of  hot  water.  When  thoroughly 
mixed,  run  into  frames  and  let  stand  overnight;  then  cut 
into  bars  and  open-pile  to  dry.  When  thoroughly  dry 
chip  and  grind;  it  is  then  ready  for  use. 


CHAPTER  VIII 
LEATHER   MANUFACTURE 

THE  object  of  tanning  is  to  render  the  skins  of  ani- 
mals imputrescible  and  pliable.  As  only  a  small  amount 
of  leather  is  required  with  the  hair  on,  it  is  necessary, 
before  entering  into  the  actual  tanning  process,  to  remove 
this  hair  by  preliminary  treatments  carried  out  to  best 
advantage  in  accordance  with  the  outline  given  below: 

312.  Soaking.  Skins  or  hides  come  to  the  tanner  in  a 
flint  dry  salted,  green-salted  or  pickled  condition,  and  con- 
tain, besides  the  salt,  a  large  amount  of  blood  and  dirt. 
The  first  step,  therefore,  is  to  place  them  in  a  pit  containing 
water,  where  they  are  allowed  to  remain  until  soft.  They 
are  then  rinsed  off  in  fresh  water  to  remove  as  much  of  the 
dirt  and  blood  as  possible.  When  washing  is  complete 
the  skins  are  placed  over  a  round,  inclined  table  called 
a  "  beam,"  where  the  excess  of  flesh,  earlaps,  tail,  etc. 
are  trimmed  off  by  means  of  a  sharp  knife  called  a 
"  flesher."  Machines  are  also  made  for  this  purpose. 

Skins  or  hides  which  come  to  the  tanner  in  the  dry- 
salted  or  dry  (flint)  condition  require  a  longer  treatment 
than  green-salted  stock.  They  are  usually  soaked  for 
about  two  days,  then  run  in  a  dry  mill  for  an  hour  or 
so,  and  returned  to  the  soak.  The  stock  should  be  in  a 
soft  condition  before  proceeding  to  subsequent  operations. 

141 


142      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

Sometimes,  in  order  to  hasten  the  process,  a  small  amount 
of  caustic  soda  or  formic  acid  is  added  to  the  soak  water, 
usually  about  o.i  per  cent  of  the  weight  of  the  water. 

313.  Depilating.  The  next  step  in  the  process  consists 
in  removing  the  hair  and  epidermis  and  is  usually  accom- 
plished by  means  of  milk  of  lime,  although  other  substances 
are  sometimes  employed. 

(a)  Milk  of  Lime  Process.  Sufficient  milk  of  lime  is 
prepared  to  cover  the  skins.  To  this,  sodium  sulphide, 
0.5  per  cent  the  weight  of  the  lime,  has  been  added.  The 
skins,  are  introduced  into  the  mixture  and  turned  twice 
each  day  in  such  a  manner  as  to  bring  the  ones  on  top 
into  the  bottom  of  the  pit.  This  treatment  requires  from 
four  to  eight  days,  depending  on  the  nature  of  the  skins, 
the  proper  time  being  indicated  by  the  ease  with  which 
the  hair  and  epidermis  come  off  when  rubbed  over  with 
the  ringer. 

The  chemical  action  taking  place  in  this  treatment 
is,  in  part,  the  combination  of  the  calcium  hydroxide 
with  the  fat  surrounding  the  hair  follicle  and  lying  be- 
tween the  fibers,  thus  forming  a  lime  soap,  which  loosens 
the  hair  and  epidermis,  swelling  up  and  separating  the 
fiber  bundles.  The  action  is  more  largely  due,  however, 
to  the  solvent  nature  of  the  lime  and  enzymes  present, 
which  tend  to  hydrolyze  and  dissolve  the  albuminous 
matter.  The  hair  itself  is  only  very  slightly  altered.  Old 
limes  will  unhair  much  more  readily  than  new  ones, 
which  is  often  advantageous  except  that,  for  sole- 
leathers  and  others  requiring  firmness,  new  limes  are 
preferred. 

When  properly  limed,  the  skins  are  removed  from 
the  pit  and  allowed  to  drain.  They  are  again  placed  over 


LEATHER  MANUFACTURE  143 

the  beam,  where  their  plump  condition  facilitates  the 
removal  of  the  remaining  flesh  with  the  fleshing  knife, 
and  also  the  scraping  off  of  the  loosened  hair  with  a 
blunt  knife.  In  the  case  of  hides  (heavy  leather)  much  of 
the  lime  is  also  worked  out  by  this  means.  After  unhair- 
ing  and  fleshing,  the  skins  or  hides  are  placed  in  a  pin-mill 
where  they  are  washed  with  running  water  for  half  an 
hour,  or  until  the  fine  hair  has  been  removed.  The 
stock  is  then  in  proper  condition  for  subsequent  treat- 
ment. 

(b)  Sulphide  Process  for  Depilating.     The  well-soaked 
and  washed  stock  is  put    into    a    paddle    containing    a 
4°  Tw.  solution  of  sodium  sulphide  at  70°  F.      It  is  run  for 
about  two  hours.     The  wheel  is  then  stopped  and,  after 
that,   turned  for  five  minutes  each  hour.     The  stock  is 
left    in    the   liquor  overnight  and    turned   from   time  to 
time  during    the  morning.     At  about  noon   the   plug  is 
drawn   and   the   spent    liquor    let   out.      The    paddle   is 
filled  with  water  and  run  for  half  an  hour.     One  per  cent 
of    sodium    bicarbonate  is  now  added   and  run  for  one 
hour.     Fresh  water  is  turned  on  and  the  stock  washed 
for  three  hours.     By  this  time  it  should   be  partly  free 
from    sulphide   and    in   a  fallen   condition.      It   is    then 
removed  from  the  paddle  and  may  be  bated  and  pickled 
as  desired. 

(c)  Depilating    with    Sodium    Sulphide    and    Calcium 
Chloride.     Into    the   paddle   put   a   weighed    amount   of 
sodium  sulphide,  sufficient  to  make  a    20°  Bk.  solution. 
To    this    solution     add     one-fourth    as    much    calcium 
chloride  as  sodium  sulphide.     Raise  the  temperature  of  the 
solution    to   about   80°   F.,  add    the  stock,  and  run  at 
intervals  during   the  day.      The    skins    are    left  in  the 


144      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

paddle  overnight,  and,  at  the  end  of  twenty-four  hours, 
washed  for  half  an  hour,  neutralized  with  2  per  cent  of 
sodium  bisulphite,  and  washed  again  for  about  an  hour. 
They  are  then  ready  for  the  bate.  The  advantage  of 
this  process  is  that  the  stock  resembles  limed  material 
and  is  very  free  from  false  grain.  Also,  the  measure- 
ment is  better  than  that  of  straight  sulphide  stock. 

(d)  Painted  Sheepskin  Pelts.  Soaking.  The  skins,  if 
not  in  a  perfectly  soft  condition,  are  placed  in  water, 
until  in  the  necessary  flaccid  state.  They  are  then  horsed 
up  to  drain. 

Painting.  Dissolve  5  Ibs.  of  sodium  sulphide  in  as 
little  hot  water  as  possible,  and  add  to  this  solution  2  Ibs. 
of  lump  lime.  As  the  limes  lakes,  the  mass  will  thicken 
to  the  consistency  of  a  heavy  cream.  If  not  quite 
thick  enough,  a  small  amount  of  lime  may  be  added. 
Hydrated  lime  may  also  be  used  with  the  sodium  sulphide, 
and  enough  added  to  produce  a  creamy  consistency. 

Treatment.  The  drained  skin  is  placed  flesh  side  up 
on  the  floor  or  table,  where  a  liberal  coating  of  the  paste 
is  applied.  It  is  then  placed  on  the  floor,  and  a  second 
skin  painted  in  the  same  manner,  is  placed  flesh  to  flesh 
on  the  previous  one.  The  next  skin  is  placed  wool 
to  wool,  and  so  on  until  the  stock  is  piled.  The  following 
day  the  skins  are  taken  up  in  order.  The  white  wool  is 
pulled  off  by  hand  and  placed  in  one  container,  and 
the  colored  wool  in  another.  During  the  pulling  of  the 
wool,  it  is  often  customary  to  sort  four  different  grades. 
The  stock  of  wool  thus  obtained  is  washed  first  in  water 
containing  5  per  cent  of  sodium  bicarbonate  or  sodium 
bisulphite,  then  in  running  water,  and  is  whizzed,  and 
dried. 


LEATHER  MANUFACTURE  145 

The  unhaired  pelts  are  placed  in  a  paddle  with  5 
per  cent  of  lime  and  run  for  two  or  three  days.  They 
are  then  bated,  pickled,  and  tanned  as  desired. 

314.  Puering  or  Bating.  This  process  frees  the  skin 
from  lime,  produces  a  soft,  flaccid,  open  condition,  and 
smooths  down  the  grain.  There  are  numerous  methods 
in  vogue,  most  of  which  depend  upon  fermentation  for 
their  beneficial  action.  Some  of  the  substances  in  use 
are  hen,  pigeon,  and  dog  manure,  sour  milk  in  the  form 
of  dermiformer,  fermenting  bran,  puerine,  oropon,  and 
many  others.  Many  non-fermenting  bates  are  also  on 
the  market,  the  most  common  of  which  is  lactic  acid. 

The  fermenting  process  has  the  advantage  over  the 
non-fermenting  of  making  the  skins  more  open,  thus  per- 
mitting a  more  uniform  combination  of  the  hide  substance 
with  the  tanning  material. 

(a)  Oakes  Bate.  An  excellent  process  and  one  which 
may  be  carried  out  with  perfect  safety  is  covered  with 
letters  patent  by  Francis  J.  Oakes,  of  New  York  City. 
It  is  as  follows:  Into  a  paddle-box  put  enough  water 
to  work  the  skins  easily.  Add  5  per  cent  of  syrup  glucose 
and  |  per  cent  of  flowers  of  sulphur,  computed  on  the 
weight  of  the  skins.  Raise  the  temperature  of  the  bath 
to  105°  F.,  add  i  Ib.  of  yeast  for  each  1000  Ibs.  of  skin 
(or,  in  small  lots,  i  yeast  cake  .for  6  small  skins),  and 
let  stand  twenty-four  hours.  The  bath  by  this  time  has 
started  active  fermentation,  and  the  skins  are  introduced, 
together  with  one-half  »the  original  amount  of  glucose 
and  sulphur.  The  skins  are  run  for  about  five  minutes, 
then  allowed  to  stand  for  one  hour.  Next  they  are  run 
again  for  five  minutes  and  the  treatment  continued 
until  a  test  with  phenolphthalein  on  a  piece  of  the  skin, 


146      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

cut  from  the  heaviest  part,  shows  that  all  of  the  lime 
has  been  neutralized.  At  this  point,  the  fibers  are  found 
to  be  well  open,  and  the  skin  soft  and  pliable,  with  a 
smooth  and  silky  grain.  The  time  required  for  this 
operation  should  be  from  six  to  eight  hours  in  the  case 
of  heavy  skins,  with  a  correspondingly  shorter  period 
for  lighter  ones. 

(b)  Dr.  Rohm's  Bate  "  Oropon  C  "  for  Regular  Packs. 
Treatment  of  the  Skins  before  the  Bate.  The  same  as  usual. 
It  is  advisable  to  wash  them  thoroughly  before  the  bate, 
in  order  to  free  them  as  much  as  possible  from  lime.  In 
the  case  of  sulphide,  neutralize  as  usual. 

Bate: 

Quantity  of  water,  same  as  usual. 

Temperature,  as  usual. 

Time  of  bating,  two  to  four  hours  for  calf  skins; 

four  to  six  hours  for  hides. 

Quantity  of  oropon,  always  figured  on  the  weight 
of  the  wet  skins  and  according  to  their  nature, 
thus: 

8-10  oz.  per  100  Ibs.  for  calf  and  split  grains; 
10-12  oz.  per  100  Ibs.  for  unsplit  hides  (used 
for  furniture,  etc.). 

The  liquor  can  be  used  over  again,  and  in  this  case 
add,  for  the  second  and  following  packs,  about  one-half 
the  quantity,  or  even  less  of  the  oropon  used  for  making 
fresh  liquor.  It  is  advisable  to  warm  up  the  old  liquor 
overnight  the  first  two  days  in  order  to  accelerate  fer- 
mentation. After  the  liquor  has  been  used  for  two  days, 
it  will  be  noticed  that  the  fermentation  grows  stronger. 


LEATHER  MANUFACTURE  147 

To  keep  it  in  control,  run  off  every  day  about  J  to 
i  foot  of  the  liquor  (more  in  summer  than  in  winter). 
Before  running  off,  stir  the  liquor  well  to  get  rid  of 
as  much  dirt  as  possible.  As  a  rule,  make  the  bate  up 
fresh  once  every  two  weeks,  but,  in  doing  so,  leave 
about  one-fourth  of  the  old  liquor  in  the  paddle. 

Bating  Process.  Always  heat  the  water  first;  then 
put  the  oropon  in  undissolved.  After  stirring  thoroughly, 
put  in  the  skins.  The  further  treatment  is  the  same  as 
usual.  Watch  the  process  closely  in  order  to  see  how  the 
skins  fall,  and  do  not  take  them  out  until  they  are  as 
low  as  desired.  In  case  they  fall  too  quickly,  reduce 
the  quantity  of  oropon  proportionately  the  next  time. 
If  they  do  not  fall  enough,  add  to  the  bate  o .  i  to  o .  2 
per  cent  of  oropon  (dissolved  in  a  bucket  of  water  and 
added  while  the  skins  are  paddled);  at  the  same  time 
raise  the  temperature  of  the  liquor,  in  case  it  has 
cooled  down  too  quickly.  If,  after  about  one  hour, 
the  skins  are  still  too  high,  repeat  this  operation 
until  a  satisfactory  result  is  obtained.  The  next  time  a 
correspondingly  higher  concentration  is  used.  If  over- 
night bating  is  preferred,  use  about  20  per  cent  less 
oropon  than  indicated  above,  and  a  temperature  of  from 
85°-9O°  F.  before  skins  are  put  in. 

Wash  the  skins  thoroughly  after  the  bate,  and  proceed 
according  to  paragraph  315. 

(c)  Dr.  Rohm's  Bate  "Oropon  A.B."  for  Limed  Goat 
Skins.  Take  30  gals,  of  water  for  each  100  Ibs.  of  skins; 
for  regular  packs  take  the  usual  quantity  of  water. 

Treatment  of  the  Skins  before  the  Bate.  The  skins  are 
washed  in  running  water  as  usual. 

Bating,  First  Liquor.    The  skins  are  first  washed  in 


148      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

an  old,  used  bating  liquor.  If  no  old  oropon  liquor  is 
available,  substitute  a  light  solution  of  4-6  oz.  oropon 
for  each  100  Ibs.  of  skins,  or  better,  wash  the  skins  in  the 
used  dog-manure  liquor. 

Temperature.  For  soft  skins  9o°-95°  F.  (before  the 
skins  are  in).  For  hard  skins,  95°-io5°  F.  (before  the 
skins  are  in). 

Second  Liquor.  In  this  liquor  the  skins  are  bated 
overnight  (put  in  about  4  o'clock,  paddled  ten  to  fifteen 
minutes,  and  left  until  the  next  morning).  In  the  morning 
they  are  paddled  again  for  fifteen  minutes  and  if  low 
enough,  taken  out.  In  preparing  the  bating  liquor, 
always  heat  the  water  first,  then  put  in  the  oropon 
without  previously  dissolving  it,  and,  finally,  put  in 
the  skins. 

Quantity  of  Oropon: 

For  South  Americans,  Brazils,  etc.,  8-10  oz.  per 

100  Ibs. 

For  Russians,  8-10  oz.  per  100  Ibs. 
For  Chinese,  12-16  oz.  per  100  Ibs. 
For  Mochas  and  Patnas,  14-16  oz.  per  100  Ibs. 
For  Northwesterns,  16-18  oz.  per  100  Ibs. 

Temperature.  95°-io5°  F.  (before  skins  are  in),  ac- 
cording to  the  nature  of  the  skins. 

In  case  the  skins  are  not  reduced  enough,  add  more 
oropon,  starting  with  about  20  per  cent  of  the  orig- 
inal quantity.  If,  after  about  an  hour,  the  skins 
are  still  too  high,  repeat  the  operation  until  the  skins 
are  as  low  as  desired.  The  next  time,  of  course,  cor- 
respondingly more  oropon  is  used.  In  bating  over- 


LEATHER  MANUFACTURE  149 

night,  the  fermentation  will  raise  the  skins  to  the  sur- 
face of  the  water,  which  action  is  desirable.  It  is  possible 
that  the  first  two  or  three  packs  will  not  come  up,  as 
the  fermentation  is  too  weak  at  the  start.  It  will 
strengthen  gradually,  however,  and  the  fourth  and  fol- 
lowing packs  will  rise  overnight. 

(d)  Martin  Dennis'  Puerine.  Take  a  clean  5o-gal.  barrel, 
remove  the  head,  put  in  25  gals,  of  water  and  heat  to  130° 
F.,  then,  while  stirring  vigorously,  put  in  100  Ibs.  puerine. 
Cover  barrel  with  an  old  burlap  bag  to  assist  in  retaining 
the  heat.  Twenty-four  hours  later,  add  10  gals,  of  water 
at  140°  F.,  stirring  vigorously.  Twenty-four  hours  later, 
add  another  10  gals,  of  water  at  140°,  stirring  vigorously. 
After  twenty-four  hours  more,  the  puerine  is  ready  for 
use.  The  barrel  will  now  be  full,  and  each  gallon  taken 
therefrom  will  contain  2  Ibs.  of  puerine. 

To  Use  the  Prepared  Puerine.  Always  stir  thoroughly 
before  taking  any  from  the  barrel. 

First  Pack.  Have  desired  quantity  of  water  in  the 
paddle,  heat  to  95°,  put  in  stock  and  then  add,  for 
every  1000  Ibs.  of  stock,  12  Ibs.  puerine  (6  gals,  of  the 
prepared  puerine). 

Second  Pack.  Use  8  Ibs.  puerine  (4  gals,  of  the  pre- 
pared) for  every  1000  Ibs.  of  stock. 

Third  Pack.  Use  6  Ibs.  puerine  (3  gals,  of  the  pre- 
pared) for  every  1000  Ibs.  of  stock. 

Fourth  and  All  Following  Packs.  Use  4  Ibs.  puerine 
(2  gals,  of  the  prepared)  for  every  1000  Ibs.  of  stock. 

Once  a  week  allow  the  puer  paddle  to  settle  about 
four  hours,  then  draw  off  from  the  top  about  one-fifth  of 
the  bating  liquor.  This  is  easily  done  by  having  a  plug 
on  the  side  of  the  pit  at  the  proper  distance  from  the  top. 


150      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

Every  three  months  clean  the  pit  out  thoroughly  by 
drawing  another  plug  from  the  bottom. 

It  is  impossible  to  explain  in  writing  how  long  the  stock 
should  be  bated.  The  stock  should  be  left  in  the  bate, 
until,  in  the  judgment  of  the  operator,  it  is  "  low " 
enough. 

The  puerine  bating  liquor  improves  with  age,  and  it 
must  not  be  expected  that  the  first  few  packs  will  be 
as  well  bated  as  the  packs  that  follow.  In  this  re- 
spect it  is  the  same  as  a  manure  bate.  When  the  bating 
liquor  assumes  a  bluish,  slate  color,  it  is  in  prime  con- 
dition. If,  at  any  time,  this  puerine  bating  liquor  sud- 
denly becomes  yellow,  it  is  an  indication  that  too  little 
puerine  is  being  used. 

(e)  Ammonium  Chloride  Bate.  Into  a  paddle  place 
ammonium  chloride,  3  per  cent  on  the  weight  of  the 
stock,  and  heat  to  90°  F.  Enter  the  pack  and  run  until 
delimed.  Toward  the  end  of  the  treatment  neutralize 
the  alkaline  condition  with  a  small  amount  of  hydro- 
chloric acid.  Before  entering  the  second  packs  and  fol- 
lowing add,  i  \  per  cent  of  ammonium  chloride,  then 
proceed  as  above.  The  bath  is  a  continuous  one. 

315.  Pickling.     On  removing  the  skins  from  the  bate 
it  is  customary  to  pickle  them  if  they  are  to  be  tanned 
by    the    one-bath    chrome    process.      For    this    purpose 
a  stock  solution  is  prepared  by  dissolving  40  Ibs.  of  salt 
in  30  gals,  of  water,  adding  5  Ibs.  of  sulphuric  acid  and 
making  the  whole  up  to  40  gals,  with  water.     Twelve  gals, 
of  this  solution  is  used  for  each  100  Ibs.  of  stock  treated; 
and  the  skins  are  run  in  the  drum  until  struck  through. 

316.  Two-bath  Chrome    on   Pickled   Sheepskins,     (a) 
Glaze   Finish.     Sodium  Dichromate  Bath.    The  bated  or 


LEATHER  MANUFACTURE  151 

pickled  stock  is  weighed  and  placed  in  the  mill,  the  door 
closed,  and  the  following  solution,  estimated  on  the  weight 
of  the  stock,  prepared: 

Sodium  dichromate,  6  per  cent 
Salt,  4  per  cent 

Hydrochloric  acid,    3  per  cent 
Water,  5  times  the  weight  of  the  stock. 

The  mill  being  set  in  motion,  the  above  solution  is 
introduced  through  the  trunnion,  and  the  stock  turned 
for  1 1  hours,  or  until  struck  through.  The  skins  are 
removed  from  the  drum  and  horsed  up  overnight  to  allow 
for  draining  and  fixation  of  the  chrome. 

Sodium  Thiosulphate  Bath.  The  following  morning  the 
skins  are  removed  from  the  horse  one  at  a  time,  dipped 
in  a  10  per  cent  solution  of  sodium  bisulphite,  and  thrown 
into  the  drum.  The  following  solution, 

Sodium  thiosulphate  (hypo),  12  per  cent 
Salt,  3  per  cent 

Hydrochloric  acid,  6  per  cent 

Water,  5  times  the  weight  of  the  stock, 

is  added  through  the  trunnion  while  the  mill  is  in  motion 
and  run  for  ij  hours,  or  until  a  robin's-egg  blue  color 
results.  The  skins  are  again  horsed  up  overnight. 

Neutralization.     The  skins,  after  standing  overnight, 
are  returned  to  the  mill  and  run  for  one-half  hour  with 

Sodium  bicarbonate,  |  per  cent 

Water,  5  times  the  weight  of  the  stock. 


152      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

The  plugs  are  now  drawn  and  the  stock  washed  for  one- 
half  hour  with  running  water.  The  skins  are  then  set 
out  and  shaved. 

Coloring.  The  wet,  shaved  stock  is  placed  in  the  drum 
with  sufficient  water  at  125°  F.  to  float  it.  One  per 
cent  of  hematine  crystals,  dissolved  in  water  at  125° 
F.  and  made  alkaline  with  ammonia,  is  introduced  through 
the  trunnion  while  the  drum  is  in  motion  and  run  for 
fifteen  minutes.  One  and  one-half  per  cent  of  Chrome 
Leather  Black  C  is  dissolved  in  water  at  140°  F.  and 
added  to  the  hematine  solution.  The  stock  is  now  run 
for  fifteen  minutes,  then  one-half  hour  longer  in  a  fat 
liquor  consisting  of 

Victoria  Fat  Liquor  BXX,  i  per  cent 
Cod  oil,  |  per  cent 

Water,  2  times  the  weight  of  the  stock. 

The  stock  is  now  washed  for  five  minutes  in  warm 
water,  removed,  set  out,  lightly  oiled  with  i  to  3  glycerine 
and  hung  up  to  dry. 

Decreasing.  Should  the  raw  stock  feel  excessively 
greasy,  it  is  best  to  dip  it  at  this  stage  in  naphtha  for 
fifteen  minutes  and  then  hang  up  to  dry  again. 

Finishing.  The  dried  skins  are  placed  in  damp  saw- 
dust overnight,  or  until  in  a  proper  sammied  condition. 
They  are  then  staked  and  tacked.  On  stripping  they 
are  trimmed,  given  a  coat  of  glaze  finish,  and  glazed 
on  the  jack.  They  are  now  lightly  staked  and  ironed. 
A  second  coat  of.  finish  is  applied  and,  when  dry,  they 
are  glazed  again. 

(b)  Mat  Finish. 

Tanning.    The  bated  or  pickled  stock,  having   been 


LEATHER  MANUFACTURE  153 

weighed,  is  placed  in  the  drum  and  the  following  solution 

prepared: 

Sodium  dichromate,  6  per  cent 
Sulphuric  acid,  2  per  cent 

Salt,  4  per  cent 

with  the  necessary  amount  of  water  to  give  proper  working 
conditions.  The  -skins  being  on  the  shelf,  the  solution 
is  placed  in  the  bottom  of  the  drum,  the  door  closed,  and 
the  power  turned  on.  The  turning  is  continued  for  about 
if  hours,  or  until  the  stock  has  become  struck  through. 
It  is  then  horsed  up  overnight  and  allowed  to  drain. 
The  next  morning  it  is  returned  to  the  drum  and  the 
following  solution  added: 

Sodium  bisulphite,  6  per  cent, 

dissolved  in  sufficient  water  to  float  the  stock.  It  is  run 
in  this  reducing  solution  for  about  one  hour  or  until  a 
robin's-egg  blue  color  results.  The  stock  is  again  horsed 
or  piled  for  twenty-four  hours,  to  allow  hydration  to 
take  place.  To  neutralize  the  excess  of  acid  run  the 
stock  with  |  per  cent  of  sodium  bicarbonate,  and  finally 
wash  well  with  running  water. 

Coloring.  The  washed  stock  is  set  out,  shaved,  and 
weighed.  One  per  cent  of  hematine  powder  is  dissolved 
in  water  at  130°  F.  and  enough  ammonia  added  to  give 
an  alkaline  reaction.  The  stock  is  placed  in  the  drum  and 
run  in  the  above  solution  for  fifteen  minutes.  Through 
the  trunnion  is  added  a  solution  containing 

Brilliant  Chrome  Leather  Black  C,  2  per  cent 

at  a  temperature  of  140°  F.  and  run  for  fifteen  minutes 
longer.  One  per  cent  of  Victoria  Fat  Liquor  B  X  X  at  140° 


154      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

F.  is  now  added,  without  removing  the  color,  and  run 
for  half  an  hour  longer.  The  stock  is  finally  removed 
from  the  drum,  set,  lightly  oiled,  and  hung  up  to  dry. 

Finishing.  The  dried  skins  are  placed  in  damp  saw- 
dust overnight  and,  when  in  the  proper  sammied  con- 
dition, are  staked  and  tacked.  On  stripping  they  are 
trimmed  and  given  a  light  staking  and  a  coat  of  mat  finish. 
The  finish  having  dried,  the  skins  are  given  a  light  coat 
of  finishing  oil  and  then  ironed. 

317.  One-bath  Chrome,  (a)  Box  Calf.  Stock:  Green- 
salted,  5-7  Ib.  calf  skins. 

Soaking.  The  stock  is  shaken  free  from  salt  and,  after 
trimming,  is  placed  in  fresh  water  for  twenty-four  hours. 

Milling.  The  excess  of  salt  and  dirt  is  removed  by 
milling  for  fifteen  minutes  with  running  water. 

Fleshing.  The  excess  of  flesh  is  removed  on  the  flesh- 
ing machine. 

Depilating'.  Five  per  cent  of  hydrated  lime  on  the 
weight  of  the  fleshed  stock  is  placed  in  the  paddle  with 
the  necessary  amount  of  water  and  i  per  cent  of  sodium 
sulphide.  The  temperature  is  raised  to  70°  F.,  and  the 
stock  entered  and  run  at  intervals  during  the  day.  The 
following  morning  a  new  portion  of  lime  and  sulphide  is 
introduced,  the  same  amount  being  used  as  on  the  first 
day.  After  two  days'  treatment,  the  bath  is  again  strength- 
ened in  the  same  manner,  the  temperature  being  main- 
tained at  70°  F.  At  the  end  of  four  days,  and  without 
further  additions,  the  stock  is  in  proper  condition  for 
unhairing. 

Unhairing.  On  removal  from  the  depilating  solution, 
the  skins  are  thrown  into  water  at  85°  F.  for  one-half 
hour,  unhaired  over  the  beam,  and  washed. 


LEATHER  MANUFACTURE  155 

Bating.  A  bath  of  oropon  is  prepared,  consisting 
of  8  oz.  of  Oropon  C  for  each  100  Ibs.  of  stock  treated. 
The  temperature  at  the  start  is  100°  F.  The  stock  is 
turned  from  time  to  time  and  allowed  to  remain  in  the 
paddle  overnight.  On  the  following  morning  the  skins 
should  be  in  a  soft  and  open  condition  and  free  from  lime. 

Pickling.  A  stock  pickle  is  prepared  by  dissolving  40 
Ibs.  of  salt  in  30  gals,  of  water,  adding  5  Ibs.  of  sulphuric 
acid,  and  making  the  whole  up  to  40  gals,  with  water. 
Twelve  gals,  of  this  solution  is  taken  for  each  100  Ibs. 
of  stock  treated,  the  latter  being  run  in  the  drum  until 
struck  through. 

Tanning.  The  drained  and  pickled  stock  is  placed  in 
the  drum  with  8  gals,  water  and  6  Ibs.  of  salt  for  each 
100  Ibs.  treated,  and  run  for  fifteen  minutes.  Six  Ibs.  of 
''  Tanolin  "  for  each  100  Ibs.  of  stock  is  dissolved  in  boiling 
water,  using  i  gal.  of  water  for  3  Ibs.  of  tanolin.  When 
the  solution  is  cool  one-third  is  added  to  the  contents  of 
the  drum  and  the  stock  run  for  one-half  hour;  then 
another  one- third,  and  another  one-half  hour  run;  finally, 
the  last  one-third  is  introduced,  and  the  drum  run  for 
one  hour.  Eight  oz.  of  bicarbonate  of  soda  is  dissolved 
in  a  little  water,  added  to  the  drum,  and  run  for  two 
hours;  then  6  oz.  per  100  Ibs.  more  bicarbonate  of 
soda  in  solution  is  added  and  the  stock  run  until 
tanned.  The  test  for  complete  tannage  is  determined 
by  boiling  a  sample  of  the  heavy  portion,  and,  if 
tanned,  it  will  not  curl.  When  tanned,  the  stock  is  horsed 
up  for  forty-eight  hours,  allowing  the  chromium  hydroxide 
to  set. 

Neutralizing.  After  draining  for  forty-eight  hours, 
the  skins  are  thrown  into  the  drum  and  a  solution  of 


156      LABORATORY  GUIDE  OF  INDUSTRIAL   CHEMISTRY 

borax  added, — i  Ib.  of  borax  in  10  gals,  of  water  for  each 
100  Ibs.  The  stock  is  milled  for  one-half  hour  and  washed 
in  running  water  for  one-half  hour.  It  is  then  removed 
from  the  drum,  set  out,  and  shaved. 

Coloring.  The  shaved  stock,  after  being  weighed,  is 
returned  to  the  drum  and  sufficient  water  at  125°  F.  added 
to  float  the  skins.  One  Ib.  of  hematine  is  dissolved  in 
10  gals,  of  water  at  125°  F.  per  100  Ibs.  of  stock,  and, 
after  being  made  alkaline  with  ammonia,  is  added  through 
the  trunnion  while  the  drum  is  in  motion,  and  run  for 
fifteen  minutes.  One  and  one-half  Ibs.  of  Chrome  Leather 
Black  C  is  dissolved  in  10  gals,  of  water  at  140°  F.  per 
100  Ibs.  of  stock,  added  to  the  contents  of  the  drum,  and 
run  for  fifteen  minutes  longer. 

Fat  Liquoring.  Two  and  one-half  Ibs.  of  Victoria  Fat 
Liquor  BXX,  dissolved  in  logals.  of  water  per  icolbs.  of 
stock,  are  added  to  the  contents  of  the  drum  without 
removal  of  the  color  solution.  The  stock  is  then  milled 
for  one-half  hour.  On  removal  from  the  drum,  the  stock 
is  set  out,  oiled  off  lightly  with  Setine  No.  2,  and  hung 
up  to  dry. 

Staking.  The  dry  stock  is  placed  in  damp  sawdust  over- 
night, when  it  is  brought  to  the  proper  sammied  condition. 
The  skins  are  then  staked  and  tacked  out.  When  dry, 
they  are  stripped  from  the  boards,  trimmed,  and  restaked. 

Finishing.  To  the  staked  leather  a  coat  of  glaze 
finish  is  applied  and,  when  dry,  the  stock  is  glazed. 
A  coat  of  finishing  oil  No.  6  is  next  applied,  and  the 
stock  ironed.  A  second  coat  of  glaze  finish  is  then 
given  and,  when  thoroughly  dry,  the  stock  is  again 
glazed.  After  the  second  glazing,  the  skins  are  boarded 
in  the  manner  usual  for  where  box  grain. 


LEATHER  MANUFACTURE  157 

One-bath  Chrome,  (b)  Mat  Calf.  Stock:  Green-salted 
calf  skins,  5-7  Ibs. 

Soaking.  The  stock  is  shaken  free  from  salt  and,  after 
trimming,  is  placed  in  fresh  water  for  twenty-four  hours. 

Milling.  The  excess  of  salt  and  dirt  is  removed  by 
washing  in  running  water  for  fifteen  minutes. 

Fleshing.  The  excess  of  flesh  is  removed  on  the  fleshing 
machine. 

Depilating.  Five  per  cent  of  hydra  ted  lime  on  the 
weight  of  the  fleshed  stock  is  placed  in  the  paddle  with 
water  at  a  temperature  of  70°  F.,  and  the  stock  entered. 
The  paddle  is  turned  from  time  to  tune,  and  the  following 
morning  another  portion  of  5  per  cent  of  hydrated  lime  is 
put  in.  A  fresh  portion  of  lime  is  added  on  each  of  the  next 
two  days,  the  temperature  being  maintained  at  about 
70°  F.  At  the  end  of  five  days,  the  skins  are  drawn 
and  should  be  in  proper  condition  for  unhairing. 

Unhairing.  On  removal  from  the  depilating  solution, 
the  stock  is  thrown  into  water  at  85°  F.  for  one-half  hour 
and  unhaired  over  the  beam. 

Bating.  A  bath  of  Oropon  C  is  prepared,  con- 
sisting of  8  oz.  of  oropon  for  each  100  Ibs.  of  stock  treated. 
The  temperature  is  100°  F.  at  the  start.  The  stock  is 
turned  from  time  to  time  and  in  the  paddle  overnight.  On 
the  following  morning  the  skins  should  be  soft,  open,  and 
free  from  lime. 

Pickling.  The  washed  skins  are  put  in  the  drum; 
and  in  a  barrel  is  placed  \  gal.  of  water  for  each  pound 
of  stock.  To  this  water  is  added  12  per  cent  of  salt  and 
if  per  cent  of  sulphuric  acid.  The  solution  thus  prepared 
is  added  through  the  trunnion  while  the  drum  is  in  motion 
and  run  for  if  hours.  The  stock  is  then  allowed  to  remain 


158      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

in  the  drum  overnight  and  run  for  another  half  hour 
the  following  morning.  It  is  next  taken  from  the  mill, 
horsed  up,  and  allowed  to  drain. 

Tanning.  The  drained,  pickled  stock  is  placed  in 
the  drum  with  8  gals,  of  water  and  6  per  cent  of  salt  and 
run  for  fifteen  minutes.  Six  per  cent  of  tanolin  is 
dissolved  in  boiling  water,  using  i  gal.  of  water  for  3  Ibs. 
of  tanolin.  Of  the  cooled  solution  one-third  is  added 
to  the  contents  of  the  drum,  and  the  stock  run  for  one- 
half  hour;  another  one- third  is  entered  and  run  for  one- 
half  hour;  finally,  the  last  one- third  is  introduced  and 
the  drum  run  for  one  hour.  Eight  oz.  of  sodium  bicar- 
bonate, dissolved  in  a  little  water,  is  added  to  the  contents 
of  the  drum  and  run  for  two  hours,  then  6  oz.  more  of 
sodium  bicarbonate  for  each  100  Ibs.  of  stock,  and  run 
until  tanned. 

Neutralizing.  After  the  skins  have  been  drained  on 
the  horse  for  forty-eight  hours,  they  are  thrown  into  the 
drum  with  a  solution  of  i  per  cent  of  borax  milled 
for  one-half  hour,  washed  for  one-half  hour,  set  out,  and 
shaved. 

Coloring.  The  shaved  stock,  after  being  weighed,  is 
returned  to  the  mill  with  sufficient  water  at  125°  F. 
to  float  the  stock.  One  per  cent  of  hematine,  dissolved 
in  water  at  125°  F.,  made  alkaline  with  ammonia,  is  added 
through  the  trunnion  while  the  drum  is  in  motion  and 
run  for  fifteen  minutes.  One  and  one-half  per  cent  of 
Chrome  Leather  Black  C  is  dissolved  in  water  at  145°  F., 
added  to  the  contents  of  the  drum,  and  run  for  fifteen 
minutes  longer. 

Fat  Liquoring.  Four  per  cent  of  Victoria  Fat  Liquor 
B  X  X  is  dissolved  in  water  at  140°  F.,  put  into  the  drum, 


LEATHER  MANUFACTURE  159 

without  removing  the  color,  and  run  for  one-half  hour,  On 
removal  from  the  drum  the  stock  is  set  out,  oiled  off 
with  Setine  No.  2,  and  hung  up  to  dry. 

Staking.  The  dry  stock  is  placed  in  damp  sawdust 
over  night  to  sammie.  It  is  then  staked  and  tacked 
out.  When  dry,  the  skins  are  stripped,  trimmed,  and 
restaked. 

Finishing.  The  staked  leather  is  given  a  coat  of 
mat  finish  and  allowed  to  dry.  A  coat  of  finishing 
oil  No.  6  is  then  applied  and  the  stock  ironed.  If  bad 
on  the  grain,  a  light  snuffing  will  improve  the  appearance 
of  the  leather. 

318.  Bright  Calf  and  Side  Leather.  Depilating.  The 
soaked  and  fleshed  stock  may  be  very  readily  depilated 
by  running  in  the  paddle,  or,  if  desired,  in  a  still-pit  with 
5  per  cent  of  hydrated  lime  and  i  per  cent  of  sodium 
sulphide,  estimated  on  the  wet,  fleshed  weight. 

By  calling  the  pits  A,  B,  and  C,  and  numbering  the 
pack,  the  method  of  procedure  may  be  more  readily 
understood.  The  temperature  should  be  maintained  at 
about  70°  F.,  and  the  process  is  as  follows: 

ist  day,  Pack  i  Entered  in  pit  A  containing  5  per  cent 
lime  and  i  per  cent  sodium  sulphide. 

2d  day,    Pack  i  Transferred  to   pit  B   containing  5  per 
cent  lime  and  i  per  cent  sodium  sul- 
phide. 
2  Entered  in  pit  A ,  once  used. 

3d  day    Pack  i  Transferred  to  C  containing  5  per  cent 
lime  and  i  per  cent  sulphide. 

2  Transferred  to  B,  solution  once  used. 

3  Entered  in  pit  A ,  solution  twice  used. 


160      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

4th  day,  Pack  i  Removed. 

3  Drawn  from  A,  new  liquor  consisting  of 
5  per  cent  lime  and  i  per  cent  sodium 
sulphide  made  up  for  that  pit. 

2  Transferred  to  A. 

3  Transferred  to  C,  once  used. 

4  Entered  in  pit  B,  twice  used. 
5th  day,  Pack  2  Removed. 

4  Drawn  from  B  and  new  liquor  prepared 
as  above. 

3  Transferred  to  B. 

4  Transferred  to  A,  once  used. 

5  Entered  in  C,  twice  used, 
oth  day,  Pack  3  Removed. 

5  Drawn   from    C,    and    new    liquor    pn: 
pared. 

4  Transferred  to  C. 

5  Transferred  to  B,  once  used. 

6  Transferred  to  A,  twice  used. 

When  once  started  and  carried  out,  the  above-mentioned 
movement  entails  only  very  little  handling  of  the  stock. 
This  method  gives  a  good  grain  and  full  feel. 

Unhairing.  On  removal  from  the  depilating  solution, 
the  stock  should  be  thrown  into  water  at  about  85°  F. 
for  one-half  hour  and  then  unhaired  on  the  machine  or 
over  the  beam. 

Bating.  The  bating  may  be  carried  out  in  the  usual 
way.  Care  must  be  taken  to  see  that  the  stock  is  not 
bated  too  low,  otherwise  a  loose  grain  may  result. 

Pickling.  A  stock  pickle  should  be  prepared  as  fol- 
lows: 


LEATHER  MANUFACTURE  161 

Salt,  40  Ibs. 

Sulphuric  acid,  5  Ibs. 

Water  sufficient  to  make  40  gals. 

Place  the  stock  in  the  drum  and  add  12  gals,  of  pickle 
for  each  100  Ibs.  of  stock.  Run  for  about  if  hours  or 
until  struck  through. 

Tanning.  The  drained,  pickled  stock  may  now  be 
tanned  by  any  method  desired. 

Coloring.  The  shaved  stock  is  weighed  and  placed 
in  the  drum  with  sufficient  water  at  125°  F.  to  float  it. 
One  Ib.  of  logwood  extract  for  each  100  Ibs.  of  shaved  stock 
is  dissolved  in  10  gals,  of  water  at  125°  F.  and  made  alka- 
line with  ammonia.  The  logwood  solution  is  then  poured 
through  the  trunnion  and  the  stock  run  for  fifteen  minutes. 
Chrome  Leather  Black  C.,  if  Ibs.  for  each  100  Ibs.  of  stock, 
is  dissolved  in  10  gals,  of  water  at  140°  F.,  added  through 
the  trunnion,  and  run  for  fifteen  minutes  longer. 

Fat  Liquoring.  A  fat  liquor  is  prepared  by  dissolving 
for  each  100  Ibs.  of  stock 

Victoria  Fat  Liquor  B  X  X,     if  Ibs. 
Water  at  140°  F.,  10    gals. 

To  this  is  added 

God  oil,  i    Ib. 

The  fat  liquor  emulsion  is  now  introduced  through  the 
trunnion  without  removing  the  color  solution  and  run 
for  one-half  hour.  The  stock  may  now  be  removed  with- 
out washing,  or,  if  desired,  a  short  washing  in  warm 
water  may  be  given. 

To  get  a  blue  black,  some  tanners  prefer  to  shave 
out  of  color.  If  this  is  done,  only  one-half  of  the  color 


162      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

required  for  shaved  stock  would  be  necessary  on  the  wet 
tanned  weight.  Nigrosine  is  then  mixed  with  the  fat 
liquor  to  cover  up  the  unevenness  produced  by  shaving. 

Finishing.  The  colored  stock,  on  removal  from  the 
mill,  is  put  out  and  hung  up  to  dry.  It  is  sometimes 
oiled  off  with  mineral  oil.  After  being  is  sammied  in 
damp  sawdust,  it  is  staked,  tacked,  stripped,  restaked,  and 
given  a  coat  of  glaze  finish.  When  dry,  it  is  jacked, 
given  a  second  coat  of  finish,  and  jacked  again.  The 
stock  may  also  be  smooth-plated  if  desired. 

319.  Glazed  Goat  Skins.  Soaking.  The  skins  are 
placed  in  water  at  60°  F.  and  allowed  to  soak  for  about 
three  days,  or  until  perfectly  soft.  They  are  then  washed 
in  the  mill  for  fifteen  minutes  with  running  water,  and 
dry  milled  for  five  minutes. 

Depilating.  The  washed  stock  is  treated  with  a  mix- 
ture of  10  per  cent  of  lime  slaked  in  the  presence  ol  i 
per  cent  of  arsenic  sulphide.  The  treatment  is  carried 
out  in  a  series  of  pits  and  usually  takes  from  twelve  to 
fifteen  days,  the  lime  being  strengthened  as  required. 
The  skins  are  then  removed  and  unhaired  over  the  beam 
or  on  the  machine,  and  subsequently  fleshed. 

Bating.  The  fleshed  stock  is  weighed,  placed  in  the 
paddle  with  £  per  cent  of  Oropon  AA  at  a  temperature 
of  100°  F.,  run  for  the  remainder  of  the  day,  and  left 
in  the  paddle  overnight.  The  next  morning  the  stock 
is  run  for  an  hour  longer,  or  until  perfectly  soft  and 
open. 

Pickling.  If  desired,  the  bated  stock  is  placed  in 
the  mill  and  pickled  for  i|  hours  with  12  per  cent  of 
salt  and  i-|  per  cent  of  sulphuric  acid,  using  a  solution 
containing  i  Ib.  of  salt  to  i  gal.  of  water. 


LEATHER  MANUFACTURE  163 

Tanning.  The  drained,  bated,  or  pickled  skins  are 
placed  in  the  mill  and  treated  with  a  solution  made  up 
as  follows,  running  for  i^  hours,  or  until  struck  through: 

Sodium  dichromate,  6  per  cent 
Sulphuric  acid,  2  per  cent 

Salt,  4  per  cent 

Water,  3  times  the  weight  of  stock 

On  removal  from  the  drum,  the  skins  are  horsed 
up  overnight  and  allowed  to  drain.  They  are  then  dipped 
one  at  a  time  in  a  10  per  cent  solution  of  sodium  bisul- 
phite and  thrown  into  the  drum.  A  solution  of 

Sodium  bisulphite,  6  per  cent 

Water,  3  times  the  weight  of  stock 

is  prepared  and  added  through  the  trunnion  while 
the  mill  is  in  motion.  The  milling  is  continued  for  i| 
hours,  or  until  the  stock  assumes  a  robin's-egg  blue  color 
throughout.  The  skins  are  then  removed  from  the  drum 
and  horsed  for  several  days.  They  are  then  pressed  or 
set  out  and  shaved. 

Coloring.  The  shaved  and  weighed  skins  are  placed 
in  the  drum  with  sufficient  water  to  float  them,  i  per 
cent  of  borax  added,  and  run  for  one-half  hour.  They  are 
then  washed  for  one-half  hour  in  running  water.  One 
per  cent  of  hematine  is  dissolved  in  water  at  125°  F., 
made  alkaline  with  ammonia,  enough  water  being  used 
to  thoroughly  float  the  stock.  The  skins  are  run  in  the 
solution  for  one-half  hour;  i|  per  cent  of  Bril.  Chrome 
Leather  Black  dissolved  in  20  gals,  of  water  at  140°  F. 
is  now  introduced  and  run  for  fifteen  minutes  longer. 

Fat  Liquoring.     The  stock  having  been  colored,   the 


164      LABORATORY   GUIDE  OF  INDUSTRIAL   CHEMISTRY 

following  liquor  is  prepared  and  added  through  the  trun- 
nion without  removing  the  color: 

Chip  soap,  1 1  per  cent 

Neatsfoot  Oil,  20°  C.  T.,  2    per  cent 
Water,  2  times  the  weight  of  stock 

and  run  for  one-half  hour.  The  skins  are  washed  for 
ten  minutes  in  warm  water,  set  out,  oiled  off  with 
i  to  3  glycerine  solution,  and  hung  up  to  dry. 

Finishing.  The  dry  skins  are  allowed  to  remain  in 
the  crust  for  several  days  and  are  then  sammied  in  damp 
sawdust  until  soft.  They  are  next  staked,  given  a  coat 
of  glaze  finish,  and  staked  again.  They  are  then  glazed, 
perched,  given  a  second  coat  of  glaze,  ironed,  and  glazed 
again. 

320.  Combination  Pig-skin  Tannage.  Soaking.  The 
green-salted  stock  is  soaked  in  water  for  twenty-four 
hours  and  then  washed  in  the  mill  for  fifteen  minutes 
with  running  water. 

Depilating.  A  4°  Tw.  sodium  sulphide  liquor  is  pre- 
pared at  a  temperature  of  80°  F.  The  stock  is  entered 
and  run  through  the  day,  being  allowed  to  remain  in 
the  paddle  overnight.  The  following  morning  the  stock 
is  run  for  one  hour,  and,  if  the  skins  are  in  the  proper  con- 
dition, the  excess  of  sulphide  is  removed.  The  paddle 
is  filled  with  hot  water,  the  skins  run  for  one-half 
hour,  and  the  water  drawn  off.  The  paddle  is  again  filled 
with  water,  2  per  cent  of  sodium  bicarbonate  introduced, 
and  the  stock  run  for  one-half  hour.  A  full  head  of  water 
is  now  turned  on  and  the  stock  washed  for  three  hours. 

Bating.  The  bate  used  for  this  stock  should  be  Oro- 
pon  A  B  and  should  consist  of  |  per  centon  the  weight  of 


LEATHER  MANUFACTURE  165 

the  stock  at  90°  F.  The  stock,  being  entered  in  the  after- 
noon, is  allowed  to  remain  overnight.  The  following 
morning  it  is  removed  and  is  ready  for  pickling. 

Pickle.  The  pickle  to  be  used  should  be  made  up 
with  8  Ibs.  of  salt  to  i  Ib.  of  sulphuric  acid,  using  12  per 
cent  of  salt  on  the  weight  of  the  stock  at  a  concentration 
of  i  Ib.  of  salt  to  i  gal.  of  water.  The  skins  are  run  in 
this  pickle  for  i  J  hours,  horsed  up  to  drain,  and  sammied. 

Degreasing.  The  sammied  stock  is  now  degreased 
with  Vacuum  Oil  Degreasing  Compound  and  allowed  to 
drain. 

Tanning.  The  weighed,  pickled,  and  ,degreased  stock 
is  placed  in  the  mill  and  a  solution  of 

Sodium  dichromate,  6  per  cent 
Salt,  4  per  cent 

Sulphuric  acid,  2  per  cent 

with  the  necessary  amount  of  water  added  through  the 
trunnion  while  the  drum  is  in  motion.  The  skins  are 
run  in  this  solution  for  ij  hours  and  then  horsed  up 
overnight  to  drain.  The  following  morning  the  skins  are 
returned  to  the  drum  and  a  solution  of 

Sodium  bisulphite,     6  per  cent 

in  the  necessary  quantity  of  water  added  and  run  for  if 
hours.  The  stock  is  again  horsed  up  overnight,  sam- 
mied, and  shaved. 

Neutralizing.  The  shaved  skins  are  weighed  and 
placed  in  the  drum,  a  solution  of  f  per  cent  of  sodium 
bicarbonate  added,  run  for  one-half  hour,  washed  for 
one-half  hour,  and  allowed  to  drain. 


166      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

Retanning.  A  solution  of  20  per  cent  quebracho 
extract,  standing  at  20°  Bk.,  is  prepared,  added  to  the 
stock  while  the  drum  is  in  motion,  and  run  for  one  hour. 
The  excess  of  liquor  being  drawn  off,  the  stock  is  washed 
for  fifteen  minutes,  a  solution  of  J  per  cent  of  tartar 
emetic  at  a  temperature  of  125°  F.  added,  and  run  for 
one-half  hour. 

Coloring.  The  stock  is  now  in  the  proper  condition 
and  may  be  colored  with  any  combination  of  basic  colors 
desired. 

Fat  Liquoring.  The  colored  and  washed  stock  is  best 
fat  liquored  by  using  3  per  cent  anhydrous  Turkey-red 
Oil  at  a  temperature  of  140°  F. 

Finishing.     The  same  as  given  under  Calf. 

322.  Quebracho-tanned  Sheepskins.  The  pickled  skins 
are  weighed  and  placed  in  the  mill.  A  solution  of  30 
per  cent  of  quebracho  extract  on  the  weight  of  the  stock 
is  prepared  at  a  concentration  of  30°  Bk.  To  this  solu- 
tion is  added  10  per  cent  of  salt  on  the  weight  of  the 
stock,  and  the  whole  added  to  the  skin  in  the  mill.  The 
mill  is  now  set  in  motion  and  run  for  i|  to  two  hours, 
or  until  skins  are  tanned.  The  plugs  being  drawn  and 
the  water  turned  on,  they  are  washed  until  perfectly 
clean.  If  desired,  the  washing  may  take  place  in  a 
separate  mill,  and  the  new  lot  of  skins  run  in  the  spent 
liquor  for  one-half  hour  to  utilize  the  unabsorbed  tan. 
The  plugs  being  drawn,  a  new  liquor  of  25  per  cent  of 
quebracho  at  30°  Bk.  with  10  per  cent  salt  will  suffice  to 
complete  the  tannage.  The  plugs  are  then  returned, 
the  above  liquor  added,  and  the  milling  continued  for 
ij  hours.  The  washed  stock  is  now  fat  liquored  with 
i  per  cent  of  anhydrous  Turkey-red  Oil  at  a  tempera- 


LEATHER  MANUFACTURE  167 

ture  of  110°  F.  for  one-half  hour,  washed  again,  set 
out,  shaved,  and  hung  up  to  dry.  When  dry  it  is 
degreased,  buffed  if  necessary,  and  colored,  in  the  follow- 
ing manner: 

Preparation  of  the  Stock.  A  very  important  factor  in 
the  coloring  of  vegetable-tanned  leather  is  the  proper 
preparatory  treatment  of  the  material.  The  stock  is 
placed  in  the  mill  and  run  in  water  for  some  time  in  order 
to  clear  the  grain.  Two  per  cent  of  sumac  is  now  added  and 
milled  for  about  one  hour.  It  is  then  washed  to  remove 
adhering  tanning  material.  Should  the  leather  be  very 
dark  in  color,  it  is  customary  to  treat  it  with  dilute 
sulphuric  or  formic  acid,  using  about  i  Ib.  of  acid  for 
each  100  Ibs.  of  water,  running  leather  in  it  for  about 
twenty  minutes.  The  excess  of  acid  is  removed  by  wash- 
ing in  running  water. 

Very  fatty  leathers  become  dirty  and  specked  and  make 
an  imperfect  product  when  finished.  In  order  to  prevent 
this  defect,  they  are  treated  with  benzine  to  remove  the 
fat.  For  leathers  that  are  not  too  fatty,  a  treatment  with 
water  containing  ^  part  of  borax  or  soda  per  1000  is 
sufficient.  After  milling,  the  goods  are  well  rinsed  and 
again  milled  for  half  an  hour  in  a  liquor  containing  12  oz. 
of  lactic  acid  per  20  gals. 

Mill  Coloring,  Basic  Colors.  The  tanned  stock  is 
introduced  into  the  mill  with  2  per  cent  of  sumac,  and 
sufficient  water  to  float  the  stock,  and  is  run  for  one-half 
hour.  One-half  per  cent  of  tartar  emetic  is  added  and  the 
milling  continued  for  one-half  hour  longer.  The  plugs 
are  drawn  and  the  stock  thoroughly  washed. 

The  color  solution  is  prepared  by  dissolving  the  neces- 
sary amount  of  color  in  water  at  115°  F.,  which  has  been 


168      LABORATORY   GUIDE  OF  INDUSTRIAL   CHEMISTRY 

made  acid  with  formic  acid  (4  oz.  per  100  Ibs.  of 
stock).  The  plugs  being  returned  to  the  drum,  suffici- 
ent water  at  115°  F.  to  float  the  stock  is  introduced, 
and  the  mill  put  in  motion.  One-third  of  the  color  solu- 
tion is  added  through  the  trunnion  and  run  for  three 
minutes;  a  second  third  is  added  and  run  for  two  minutes; 
and  finally,  the  last  portion  is  introduced.  The  stock  is 
then  run  for  one-half  hour,  washed  thoroughly,  and  nour- 
ished with  i  to  4  per  cent  of  Turkey-red  Oil.  On  re- 
moval from  the  drum,  the  stock  is  set  out  carefully.  Some- 
times it  is  advisable  to  oil  off  before  setting.  This  is 
done  with  a  mixture  of  neatsfoot  oil  and  glycerine  applied 
before  the  stock  is  set  out. 

Paddle  Coloring,  Basic  Colors.  The  stock  is  most 
conveniently  retanned  in  a  drum  and  the  color  set  by 
means  of  tartar  emetic  or  potassium  titanium  oxalate, 
as  described  above.  In  preparing  the  color  solution  in 
the  paddle,  the  necessary  amount  of  water  at  115°  F.  is 
introduced  and  4  oz.  of  formic  acid  for  each  100  Ibs. 
of  stock  added.  With  the  paddle  in  motion,  the  wet 
skins  are  entered  in  a  spread  condition  and  run  for  one- 
half  to  one  hour,  or  until  of  the  required  depth  of  color 
is  obtained.  On  removal,  they  are  oiled,  if  desired,  and 
set  out. 

Tacking.  The  skins,  which  have  been  well  set  out, 
are  tacked  on  the  frames,  care  being  taken  to  get 
all  the  spread  that  is  possible.  When  dry,  they  are 
stripped,  and  may  be  finished  as  desired. 

Roll  Finish.  A  flaxseed  liquor  is  prepared  by  boiling 
i  Ib.  of  flaxseed  in  3  gals,  of  water  and  straining  off  the 
solid  portion.  The  liquor  thus  prepared,  when  cold,  is 
applied  by  means  of  a  sponge  to  the  grain  side  of  the 


LEATHER  MANUFACTURE  169 

stock.  Before  the  stock  has  become  dry  it  is  rolled, 
brushed,  and  staked.  A  coat  of  leather  seasoning  is 
applied,  and,  after  the  stock  has  dried,  it  is  rolled  again. 
This  treatment  produces  a  bright  finish  that  usually  suffices 
for  this  grade  of  stock. 

Glaze  Finish.  Should  a  higher  glaze  be  desired,  the 
stock  may  be  jacketed  after  the  application  of  the  leather 
seasoning. 

Ooze  Finish.  In  preparing  the  stock,  great  care  must 
be  taken.  For  this  variety,  either  the  grain  or  flesh  side 
may  be  finished,  although  the  flesh  side  is  preferable. 
The  tanned  stock,  after  drying,  is  carefully  buffed  on  the 
flesh  side,  first  using  coarse,  and  then  very  fine  emery 
on  the  wheel.  The  leather  may  be  colored  as  given  above, 
washed  and  fat  liquored  with  i  per  cent  of  anhydrous 
Turkey-red  Oil,  carefully  set  out  on  the  flesh  side,  and 
tacked.  On  removal  from  the  boards,  the  skins  are 
trimmed,  staked  lightly,  blocked,  and  dry  milled. 

323.  Dark  Tan  Chrome.  The  following  formula  may 
be  used  on  calf  or  side  leather.  The  proportions  given 
are  for  100  Ibs.  shaved  weight. 

Coloring.  The  washed  stock  is  run  for  one-half  hour 
in  the  mill  with 

Fustic  (powdered)  3  Ibs. 

Water,  30  gals. 

at  a  temperature  of  125°  F. 
A  solution  of 

Titanium  potassium  oxalate,    4  oz. 
Water,  10  gals. 


170      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

is  prepared  at  a  temperature  of  125°  F.,  added  through 
the  trunnion  to  the  contents  of  the  mill,  and  run  for 
fifteen  minutes  longer.  The  stock  is  then  washed  for 
five  minutes  with  warm,  running  water  (temperature 
about  125°  F.),  and  the  color  solution  prepared  with 

Flavo-phosphine  G  G  Cone.   22  oz. 
Vesuvine  R,  3  oz. 

Methylene  blue  B,  i  oz. 

Water  at  140°  F.,  40  gals. 

Ten  gals,  of  water  at  150°  F.  is  added  to  the  stock,  the 
door  is  closed,  and  the  mill  set  in  motion.  One-third  of 
the  color  solution  as  prepared  above  is  strained  and  added 
through  the  trunnion;  at  the  expiration  of  five  minutes, 
a  second  portion  of  the  strained  color  is  introduced ;  and, 
after  three  minutes,  the  final  stained  portion.  The  stock 
now  run  for  one-half  hour,  the  excess  color  solution  removed, 
the  stock  washed,  and  the  following  fat  liquor  intro- 
duced through  the  trunnion: 

Victoria  Fat  Liquor  B  X,   3  Ibs. 
Ammonia,  6  oz. 

Egg  yok,  i  Ib. 

Water  at  100°  F.,  20  gals. 

running  for  one-half  hour  longer. 

The  stock  should  be  washed  with  warm  water  until 
clear,  then  set  out  carefully,  and  hung  up  to  dry. 
The  dried  stock  is  sammied  by  dipping  in  hot  water 
and  placing  in  piles  overnight,  or  until  soft.  The  damp 
stock  is  staked  and  tacked.  After  drying  on  the  boards 
the  stock  is  stripped,  trimmed,  restaked,  given  a  coat 


LEATHER  MANUFACTURE  171 

of  flaxseed  liquor,  and,  while  yet  damp,  brushed  and 
rolled.  A  coat  of  leather  season  is  then  applied,  and 
the  stock  dried,  brushed,  and  rolled. 

324.  Acid  and  Direct  Colors  on  Chrome-tanned  Leather. 
The  tanned  and  shaved  stock  is  placed  in  the  drum  with 
the  necessary  amount  of  water  to  float  the  skins  at  a  tem- 
perature of  140°  F.,  and  the  mill  set  in  motion.  A  solu- 
tion of  borax,  using  i  per  cent  on  the  weight  of  the  stock, 
is  prepared,  added  through  the  trunnion,  and  run 
for  one-half  hour.  The  plugs  are  now  drawn  and  the 
stock  washed  in  warm  running  water  for  fifteen  minutes. 
The  plugs  being  returned,  the  stock  is  floated  with  water 
at  125°  F.,  and  3  per  cent  of  developed  fustic  dissolved 
in  water  at  the  same  temperature  introduced.  After 
running  the  stock  for  one-half  hour  in  the  fustic,  the 
excess  of  liquor  is  drawn,  and  J  per  cent  of  titanium  oxalate 
at  140°  F.  added  to  the  contents  of  the  drum  and  run  for 
fifteen  minutes.  (For  light  shades  tartar  emetic  may  be 
used  in  place  of  the  titanium  salt.) 

The  skins  being  washed  from  the  titanium  salt,  a  dye- 
bath  is  prepared,  using,  for  example,  the  following 
colors : 

Fast  Leather  Yellow  RXX,  i  per  cent 
Fast  Leather  Brown  R,  i  per  cent 
Fast  Leather  Red  B,  J  per  cent 

in  water  which  has  been  softened  with  i  per  cent  of  borax 
at  a  temperature  of  140°  F.  Sufficient  water  at  140°  F. 
to  float  the  stock  is  placed  in  the  drum,  the  latter  set 
in  motion,  and  the  above  color  solution  introduced  hi 
three  portions.  After  the  stock  has  run  for  one-half 
hour  with  the  color,  3  per  cent  of  formic  acid  diluted 


172      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

with  water   is  slowly  added   and  run  for  fifteen  minutes 
longer.     The  excess  of  color  is  next  drawn. 
Now  prepare  a  fat  liquor  by  dissolving 

Anhydrous  Turkey-red  Oil,  2  per  cent 

in  water  at  140°  F.  and  add  this  also  to  the  contents 
of  the  drum,  running  for  one-half  hour.  Next,  remove 
the  plugs,  wash  well  with  warm  water,  horse  up,  set  out, 
hang  up  to  dry,  sammie  by  dipping  in  hot  water,  mill, 
stake,  and  tack.  The  stock  may  then  be  finished  as 
desired. 

325.  Fast  Brown  on  Chromed-tanned  Calf  or  Side 
Leather.  The  well-neutralized  stock  is  run  for  half  an 
hour  with  5  per  cent  of  gambia  extract,  or  3  per  cent  mat 
gambia,  at  a  temperature  of  125°  F.  One-half  per  cent 
of  titanium  potassium  oxalate  at  a  temperature  of  140° 
F.  is  introduced  and  run  for  one-half  hour  longer.  The 
stock  is  washed  for  five  minutes  with  warm  running 
water  and  drained.  Sufficient  water  at  140°  F.  to  float 
the  stock  is  placed  in  the  drum  and  i  per  cent  of  borax 
added.  The  drum  being  set  in  motion,  the  following  color 
solution  is  added  in  three  portions  and  run  for  one-half 
hour: 

Water,  3  times  the  weight  of  stock 
Borax,  |  per  cent 

Fast  Leather  Brown  2  R,  |  per  cent 

Fast  Leather  Yellow  R  W  powd.,  i|  per  cent 
Sodium  Bichromate,  \  per  cent 

After  running  in  the  above  color  for  one-half  hour, 
3  per  cent  of  formic  acid  in  a  small  amountj  of  water  is 
introduced  through  the  trunnion  and  run :  for  one-half 


LEATHER  MANUFACTURE  173 

hour.  The  excess  of  color  solution  is  now  drawn;  2| 
per  cent  of  anhydrous  Turkey-red  Oil  dissolved  in  water 
at  1 60°  F.  is  added,  and  the  mill  turned  for  one-half  hour. 
The  plugs  being  again  drawn,  the  stock  is  washed  with 
running  water,  set  out,  dried,  and  finished  in  the  usual 
manner. 

326.  Letters  on  Colors. 

B Blue 

R Red 

YorG... Yellow 

S Acid 

D Direct 

F Fast  to  light 

FF Extra  fast  to  light 

0 Concentrated 

Primary  Colors. 

Blue + Ysllow + Red  =  Black. 
Secondary  Colors. 

Blue+ Yellow  =  Green. 
Blue + Red  =  Violet. 
Yellow + Red  =  Orange. 

The  addition  of  the  third  complementary  color  to  the 
above,  when  properly  balanced,  produces  gray,  or  the  tone 
is  grayed  or  softened  by  a  smaller  amount.  Thus: 

Blue+Red+ Yellow  =  Gray. 
Red + Green  =  Gray. 
Blue+ Orange  =  Gray. 
Yellow+ Violet  =  Gray. 


174      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

327.  Harmony  of  Colors. 
Scarlet  with  Blue  or  Green. 

Gold  or  Yellow  with  Blue  or  Violet. 
Violet  with  Light  Green  or  Yellow. 
Blue  with  Yellow  or  Red. 
Carmine  with  Green  or  Orange. 
Brown  with  Blue  or  Red. 
Wine  with  Yellow  or  Green. 
Rose  with  Light  Blue  or  Yellow. 
Orange  with  Violet  or  Blue. 
Blue  Gray  with  Buff  or  Pink. 
Olive  Green  with  Red  or  Orange. 
Flesh  with  Blue  or  Dark  Green. 
Dark  Green  with  Crimson  or  Orange. 
Light  Green  with  Rose  or  Violet. 
Light  Brown  with  Blue  or  Green. 

328.  Rule  for  Mixing  or  Blending. 
Rose,  Diluted  Magenta. 

Brick  Red,  Brown  and  Magenta. 

Golden  Brown,  Yellow  and  Brown. 

Wine,  Purple  and  Magenta. 

Royal  Purple,  Magenta  and  Light  Blue. 

French  Red,  Magenta  and  Flesh. 

Navy  Blue,  Purple  and  Blue. 

Plum,  Magenta  and  Blue. 

Drab,  Yellow  and  Purple. 

Myrtle  Green,  Blue  and  Gieen. 

Landscape  Green,  Blue  and  Yellow,  or  Green  and  Yellow. 

329.  Colors  of  Different  Shades. 
Red  B+Blue  R  =  Violet. 

Red  B+Orange  =  Red  S. 


LEATHER  MANUFACTURE  175 

Red  G+ Yellow  R  =  Orange. 
Red  G+ Violet  =  Red  B. 
Blue  R + Red  B=  Violet. 
Blue  R  + Green  G  =  Blue  G. 
Blue  G+Violet  =  BlueR. 
Blue  G+ Yellow  B  =  Green. 
Yellow  R+Red  G  =  Orange. 
Yellow  R  -I-  Green  =  Yellow  G. 
Yellow  B+ Orange  =  Yellow  R. 
YeUow  B  +Blue  G  =  Green. 

330.  Alum  Tannage  for  Pickled  Sheep.    Triturate  5 
per  cent  of  flour  with  a  small  amount  of  water.     Dissolve 
3  per  cent  of  sulphate  of  aluminium  and  2  per  cent  salt 
in  20  per  cent  of  water.     Slowly  add  to  this  J  per  cent  of 
sodium  bicarbonate,  and  then  mix  in  i|  per  cent  of  egg 
yolk  and  o.i  per  cent  of  olive  oil.     Add  the  flour  paste 
and  drum  for  two  hours.      Pile  up  in  liquor    overnight 
and  then  dry  at  a  moderate  temperature.    Stake,  buff,  drum 
with  i  per  cent  egg  yolk  and  5  per  cent  French  chalk.     Set 
out,  tack,  and  dry.    Season  with  flaxseed  and  milk,  size  with 
egg  albumen,   and  iron,  or  glaze.     Use  shellac   finish   if 
desired. 

331.  Buckskin  Leather.     Triturate  5  per  cent  of  flour 
with   a   small  amount   of  water.      Dissolve   3   per   cent 
of  sulphate  of  aluminium  and  2  per  cent  of  salt  in  20  per 
cent  of  water.     Slowly  add  to  this  J  per  cent  of  sodium 
bicarbonate,  mix  in  i^  per  cent  of  egg  yolk  and  o.i  per 
cent  of  olive  oil.     Now  add  the  flour  paste.     The  skins 
being  placed  in  the  drum,  the  above  mixture  is  introduced, 
the  stock  run  for  two  hours,  then  left  in  the  liquor  over- 
night.    The   following  morning  the   mill  is  run  for  one- 


176      LABORATORY   GUIDE   OF  INDUSTRIAL   CHEMISTRY 

half  hour,  the  excess  of  liquor  drawn,  and  a  solution 
of  10  per  cent  of  gambia  at  19°  Bk.  and  10  per  cent 
of  salt  introduced.  The  mill  is  run  for  i|  hours.  The 
stock  is  now  washed,  fat  liquored  with  2  per  cent 
of  anhydrous  Turkey-red  Oil,  set  out,  and  hung  up  to 
dry.  When  perfectly  dry,  the  stock  is  staked,  buffed, 
retanned  with  5  per  cent  of  gambia,  washed,  set  out, 
oiled  off  with  glycerine,  and  tacked.  On  stripping,  the 
stock  is  given  a  light  coat  of  flaxseed  liquor,  to  which 
has  been  added  half  the  quantity  of  milk,  rolled  while 
damp,  staked,  dried,  restaked,  and  blocked. 

332.  Acid  Hemlock  Sole  Leather.     The  beamed  stock 
is  placed  in  the  rocker  with  a  5°  Bk.  hemlock  extract  to 
which  has  been  added  0.6  per  cent  of  sulphuric  acid. 
The  stock  is  allowed  to  remain  in  this  liquor  for  about 
seven  hours,  when  it  should  be  sufficiently  plump  to  trans- 
fer to  the  first  tail  liquor  of  the  yard.     The  tail  liquor 
should  stand  at  8°  Bk.  and  then  by  stages  should  be  raised 
to   about   1 6°  Bk.     In   the  handlers  it  should  go  from 
18°  to   26°  Bk.   and  in  the  layers  the  liquor  should  be 
at  40°  Bk.     The  stock  should  remain  in  the  rockers  for 
eight  days,  in  the  handlers  sixteen  days,  and  in  the  layers 
twenty  days.     On  removal  from  the  layers,  the  hides  are 
run  in  the  mill  with  100°  Bk.  quebracho  extract  for  about 
two  hours  and  then  piled  down  for  two  days.     The  stock 
is  now  stripped  with    2    per  cent   of   borax,   neutralized 
with  \  per  cent  of  sulphuric  acid,  washed,  run  in  sumac  at 
50°  Bk.,  washed,  set   out,  filled  with  sugar  and  Epsom 
Salts,  oiled  off  with  cod  oil,  dried,  sammied,   rolled,  and, 
when  dry,  rolled  again. 

333.  Union  Sole  Leather.    Soaking.    The  green-salted 
hides  are  shaken  free  from  salt,  trimmed,  and  cut  into 


LEATHER  MANUFACTURE  177 

sides.  The  sides  are  thrown  into  water,  where  they  are 
allowed  to  remain  for  twenty-four  hours.  They  are  then 
removed  from  the  water,  placed  in  the  drum,  and  turned 
for  one-half  hour.  If  not  sufficiently  soft,  they  are  again 
returned  to  the  still-soak  for  another  day. 

Liming.  In  liming  this  grade  of  stock,  the  hides  are 
first  treated  with  a  mixture  of  10  per  cent  of  hydrated 
lime  and  2  per  cent  of  sodium  sulphide,  and  left  in 
the  liquor  for  one  day.  On  the  second  day  they  are  trans- 
ferred to  another  paddle  or  pit  containing  10  per  cent 
of  lime  and  i  per  cent  of  sodium  sulphide.  On  the  third 
day  the  hides  are  transferred  to  straight  lirne  liquor  con- 
taining 10  per  cent  on  the  weight  of  stock.  On  the  fourth 
and  fifth  days  they  are  also  changed  to  straight  lime. 
On  the  sixth  day  they  are  thrown  into  the  warm  pool 
for  half  an  hour,  after  which  they  are  ready  for  unhairing. 

Unhairing.  On  removal  from  the  warm  pool,  the 
sides  are  placed  on  a  table,  spotted  for  white  hair,  and 
then  the  remainder  of  the  hair  removed  by  the  unhairing 
machine  or  over  the  beam. 

Fleshing.  The  unhaired  stock  is  next  fleshed  on  the 
machine  and  thrown  into  a  wash-paddle  for  one-half 
hour.  It  is  subsequently  skudded  on  the  beam,  then 
placed  on  sticks  and  put  into  0.6  per  cent  solution  of  lactic 
acid  overnight. 

Rockers.  On  removal  from  the  acid  liquor  the  sides 
are  placed  in  the  tail  rocker  liquor,  which  consists  of  an 
8°  Bk.  solution  of  70  per  cent  hemlock  extract,  20  per 
cent  chestnut  extract,  and  10  per  cent  myrabolans,  with 
an  acidity  of  0.6  per  cent.  The  liquor  is  changed  from 
day  to  day  until,  by  pressing  forward,  it  increases  in 
strength  to  12°  Bk.  This  should  take  fourteen  days. 


178      LABORATORY  GUIDE  OF  INDUSTRIAL   CHEMISTRY 

First  Layer.  The  stock,  as  it  comes  from  the  head 
rocker,  is  placed  in  the  first  layer  liquor  where  it  is  fur- 
ther tanned  in  a  mixture  of  50  per  cent  of  hemlock  and 
50  per  cent  of  chestnut,  standing  at  20°  Bk.  The  liquors 
are  pressed  forward  for  twenty  days,  the  stock  coming 
out  of  a  25°  Bk.  solution. 

Second  Layer.  The  second  layer  is  made  up  of  straight 
chestnut  extract  at  30°  Bk.,  and  the  stock  remains  in  it 
for  seventeen  days.  As  the  sides  are  thrown  into  the 
pit,  each  one  is  sprinkled  over  with  chestnut  oak  bark  chips. 

Third  Layer.  The  third  layer  liquor  is  made  up  of 
a  40°  Bk.  ordinary  quebracho  extract,  and  the  stock  is 
piled  down  in  it  for  thirty  days. 

Hot  Liquor.  As  the  hides  are  removed  from  the  last 
layer,  they  are  thrown  into  a  warm  40°  Bk.  quebracho 
liquor  for  about  one  hour  and  then,  after  pressing,  are 
transferred  to  the  mill. 

Extracting.  After  the  hides  have  been  placed  in  the 
mill,  a  100°  Bk.  ordinary  quebracho  extract  at  130°  F. 
is  introduced,  using  a  sufficient  quantity  to  give  2  Ibs. 
of  extract  to  a  side.  The  stock  is  run  in  the  liquor  or  ex- 
tracted for  one  hour. 

Tempering.  From  the  extract  mill  the  stock  is  thrown 
into  a  tempering  pit  containing  40°  Bk.  clarified  que- 
bracho extract  and  allowed  to  remain  for  four  days. 

Bleaching.  The  stock  from  the  tempering  pit  is  placed 
on  sticks  and  dipped  for  five  minutes  in  a  warm  i  per  cent 
solution  of  sodium  carbonate,  followed  with  a  five  min- 
utes' dip  in  warm  water,  then  in  a  i|  per  cent  solution 
of  sulphuric  acid,  again  in  a  ^  per  cent  solution  of  sul- 
phuric acid,  and  finally  in  warm  water.  From  the  bleach 
the  stock  is  again  pressed  and  is  ready  for  filling. 


LEATHER   MANUFACTURE  179 

Filling.  To  the  stock  in  the  drum  is  added  a  strong 
solution  of  2  Ibs.  of  glucose  syrup,  i£  Ibs.  of  mag- 
nesium sulphate,  and  i  Ib.  of  sole  leather  oil  for  each 
side.  The  hides  are  then  run  in  this  compound  for  one- 
half  hour. 

Drying.  Sole  leather  should  be  dried  out  very  slowly 
by  placing  it  in  a  cold,  dark  loft.  After  two  days  the 
temperature  may  be  raised  if  desired. 

Sammie.  The  dried  sides,  on  removal  from  the  loft,  are 
dipped  in  a  warm,  dilute  solution  of  glucose  and  mag- 
nesium sulphate  and  piled  down  overnight. 

Rolling.  The  wet  stock  is  given  a  liberal  coat  of 
sole  leather  sponging  compound  and  then  rolled  while 
still  wet.  This  should  be  done  in  the  morning  so  that 
the  stock  may  again  be  rolled  in  the  afternoon  when  dry. 

Brushing.  Many  tanners  do  nothing  more  after  rolling, 
but  some  prefer  to  apply  a  coat  of  brushing  compound, 
and,  when  this  is  dry,  pass  the  stock  through  the  brushing 
machine. 

334.  Patent  Leather  Daub.  (For  heavy  leather,  bark 
or  chrome  sides.) 

For  the  "  sweet-meat  "  coat  (called  the  "  short-daub  "), 
boil  40  Ibs.  linseed  oil  to  200°  F.,  add  i  Ib.  burnt 
umber,  and  run  temperature  up  to  600°  F.  Hold  tem- 
perature at  600°  until  "  long  daub"  is  obtained,  not  quite 
ready  to  break.  Then  cool  to  525°  F.  Hold  at  525° 
F.  until  it  breaks  short  from  ladle,  then  take  off  from  the 
fire  and  let  stand  until  it  forms  a  jelly  (takes  only  a  few 
minutes).  Now  add  70  gals,  of  63°  naphtha  at  nearly 
40o°-5oo°  F.  When  naphtha  is  added,  break  up  all 
big  lumps  ("  cat-heads  ")  with  fork;  stir  jelly  until  all 
lumps  are  out.  Color  with  4  Ibs.  lampblack. 


180      LABORATORY  GUIDE  OF  INDUSTRIAL   CHEMISTRY 

The  foregoing  is  the  "  slicker  coat."  For  the  second 
coat  use  either  slicker,  brush,  or  sponge;  then  apply 
the  finish  coat  of  varnish  as  for  Japan  kid  below.  If  the 
first  coat  of  varnish  does  not  look  well,  apply  light  coat 
of  varnish  on  top  of  the  finish. 

Dry  the  daub  coat  in  the  sun;  the  second  coat  in  the 
steam  oven  at  150°  F.  for  twelve  hours;  then  in  the  sun 
to  finish. 

335.  Long  Daub  for  Japanning  Kid.  Boil  to  550°  F. 
40  gals,  aged  linseed  oil  (Kellogg  &  Crave  aged  linseed 
oil).  Hold  there  until  it  will  pull  about  12  ins.,  then  cool 
down  to  130°  F.  (If  oil  curdles  while  boiling,  add  a  little 
castor  oil.)  Add  18  gals,  amyl  acetate  and  stir  until 
cold.  The  above  is  ready  for  use  at  any  time. 

First  Coat.  Take  of  the  foregoing  "  long  daub " 
i  gal.  Add  2  gals.,  8  or  9  oz.,  "  cotton  solution."  Add 
amyl  acetate  to  make  the  specific  gravity  equal  24°  Be. 
at  60°  F. 

Second  Coat.  Same  as  first  coat,  only  reduce  specific 
gravity  to  26°  Be. 

For  coloring  use  A.  A.  Blue. 

Varnish  for  the  above: 

40  gals,  aged  Linseed  Oil.     Heat  to  300°  F., 
loj  Ibs.  China  Blue. 

Run  heat  up  to  600°  F.  Hold  temperature  until  you 
get  a  varnish;  then  let  cool  down  till  cold.  Add  benzine 
and  turpentine  (or  "  Turpsine  ")  to  make  specific  gravity 
equal  38.  Let  varnish  stand  one  week  before  using. 
Apply  with  sponge.  Dry  this  varnish  coat  in  oven  twelve 
hours  at  150°  F. 


LEATHER  MANUFACTURE  181 

336.  One-bath  Chrome  Liquor  No.  1.      Chrome  alum 
25  parts,  sal-soda,  5  parts,  or  until  Congo  paper  is  turned 
blue.     To  keep  the  stock  well  open,  it  may  be  advisable 
to  add  about  2  per  cent  of  salt. 

337.  One-bath  Chrome  Liquor  No.  2.     Dissolve 

Sodium  dichromate,        10  Ibs.  in 
Water,  8  gals,  and  add 

Sulphuric  acid  10  Ibs. 

Now  introduce  slowly 

Syrup  glucose,  6  Ibs. 

This    solution    should    be    made    up    to    20    gals,    with 
water. 

338.  One-bath  Chrome  Liquor  No.  3.     Dissolve 

Sodium  dichromate,        10  Ibs. 
Salt,  10  Ibs. 

Water,  8  gals. 

Add  to  this  solution 

Sulphuric  acid,  5  Ibs. 

Sodium  bisulphite,  10  Ibs.,  dry 

Make  up  to  20  gals,  with  water.     This  liquor  contains 
J  Ib.  of  dichrome  per  gallon. 

339.  One-bath  Chrome  Liquor  No.  4. 

Sodium  dichromate,  10  Ibs. 

Water,  10  gals. 

Glycerine,  6  Ibs. 

Sulphuric  acid,  10  Ibs. 

Make  up  to  20  gals,  with  water. 


182      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

340.  Mat  Calf  Finish.     Boil  for  one-half  hour 

Irish  moss,  i  Ib. 

Potassium  ferrocyanide,    3  oz. 
Water,  3  gals. 

Strain;  then  add  f  Ib.  of  flour,  mixed  to  a  paste,  and  boil 
again.  To  this  add  5  oz.  of  nigrosine  and  make  up  to 
5  gals,  with  water. 

341.  Gun  Metal  Finish.     Boil  for  one-half  hour 

Nigrosine,  6  oz. 

Flaxseed,  8  oz. 

Chip  soap,  8  oz. 

Water,  4  gals. 

When  cool,  strain  and  add  water  to  make  8  gals.  Give 
stock  first  finish  of  glaze,  then  iron,  then  coat  of  above  finish, 
and  hang  up  to  dry.  If  harder  finish  is  desired,  add  4  oz. 
of  casein  and  2  oz.  of  ammonia  together  with  the  above. 

342.  Gun  Metal  and  Glaze  Finish.     First  make  stock 
of  nigrosine  liquor  by  dissolving  i  Ib.  of  nigrosine  in  i  gal. 
of  boiling  water.     Now  make  up  a  lactic  acid  wash  with 
2  qts.  of  lactic  acid  to  4  gals,  of  water.     Add  to  this  i 
pt.  of  nigrosine  stock. 

For  the  glaze,  to  make  4  gals.,  take 

First  Finish  for  Glaze. 
Stock  nigrosine, 

Logwood  liquor  (2  gms.  in  i  qt.) 
Water, 

Glycerine  solution  (i  to  4)' 
Blood  (2  gms.  dry  in  i  qt.) 
Alcohol, 


LEATHER  MANUFACTURE  183 

Top  Finish  for  Gun  Metal. 

First  finish,  2  gals. 

Water,  ij  gals. 

Milk,  i  qt. 

Alcohol,  i  qt. 

Glycerine,  4  ozs. 
Leather  yellow,  J  oz. 

or  enough  to  make  a  dark  green  tint. 
Top  Finish  for  Glaze. 

First  finish,  3  gals. 

Water,  i  gal. 

If  stock  is  oily,  add  a  little  lactic  acid.  If  it  is  desired 
to  keep  the  stock  solutions,  add  2  oz.  of  white 
arsenic,  or  2  oz.  of  formaldehyde  with  a  little  almond 
oil  extract. 

Stock  nigrosine,  i  qt. 

Logwood,  J  oz.  in 

Water,  i  qt. 

Blood  albumen,  i  qt. 

Milk,  i  qt. 

If  high  glaze  is  desired,  omit  the  milk  and  add  i 
more  quart  of  blood.  Then  add  6  ozs.  of  glycerine 
in  i  qt.  of  water.  Now  add  sufficient  water  to  make 
3f  gals,  and  then  i  qt.  of  denatured  alcohol.  The 
foregoing  formula  should  be  put  together  in  the  following 
order: 


184      LABORATORY   GUIDE  OF  INDUSTRIAL  CHEMISTRY 

First  Finish  for  Gun  Metal. 

Stock  nigrosine,  i  qt. 

Logwood  solution,  i  qt. 

Water,  10  qts. 

Glycerine  solution,  i  qt. 

Milk,  i  qt. 

Blood,  i  qt. 

Alcohol,  i  qt. 


1 6  qts. 

343.  Mat  Finish.     Soak  overnight 

Irish  moss,  J  Ib. 

Gum  tragacanth,  i  oz.  in 

Water,  |  pail 

Dissolve  in  the  above  after  straining 

Logwood,  6    oz. 

Neut.  chrome,  i    oz. 

Corvaline,  2    oz. 

Diamond  green,  \  oz. 

Bark  extract,  3    oz. 

Now  boil  for  about  one  hour,  strain,  and  use  when  cool. 

344.  Russia  Soap  Finish.     The  following  is  for  50  gals, 
of  finish: 

White  chip  soap,  4!  Ibs. 

White  glue,  3    Ibs. 

Egg  albumen,  i£  Ibs. 

Birch  oil,  2    Ibs. 

Flaxseed  liquor,  2    Ibs. 


LEATHER  MANUFACTURE  185 

345.  Patent  Brilliant  Finish.     For  50  gallons  use 

Nigrosine,  6|  oz. 

Corvaline,  IY&  oz. 

Methylene  blue,  \  oz. 

Gelatin,  6J  oz. 

Prepared  blood  2  Ibs.  5^  oz. 

Ammonia,  2    oz. 

Give  one  coat  and  glaze,  then  second  coat  and  glaze  again. 
Oil  off  with  mineral  oil.  A  good  oil  for  oiling  off  mat 
finish  is  mineral  seal  oil  to  which  a  small  amount  of  olive 
and  birch  tar  oil  has  been  added. 

346.  Glaze  Finish.     Dissolve  4  oz.  of  hematine  crys- 
tals in  i  gal.  of  boiling  water,  add  i^  oz.  of  fustic  extract 
and  3   oz.   of  nigrosine.     In  a  separate  vessel  soak  up 
overnight  \\  oz.  of  blood  albumen  in  i  qt.  of  water.     Make 
up  a  gum  tragacanth  paste,  60-1000,  and  add  i  pt.  of 
it  to  the  logwood  solution.     Make  up  a  flaxseed  liquor 
by  boiling  i  Ib.  of  flaxseed  in  3  gals,  of  water,  and  add  \ 
pt.    to    the    above.      Finally,    add    the    blood    albumen 
solution  to  the  mixture  when  cold  and  strain   through 
muslin. 

To  preserve  the  above  put  in  \  oz.  of  carbolic  acid  or 
i  oz.  of  birch  tar  oil.     Make  up  to  3  gals,  before  straining. 

347.  Cotton  Finish.     Mix  together  to  a  smooth  jelly 

Flexible  compound,  i    pt. 

Soluble  cotton,  \  pt,  16  oz. 
Dissolve  \  oz.  of  Japan  black  in 

Alcohol,  i  pt. 

Amyl  acetate,  i  qt. 

Benzole,  i  pt. 


186      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

Now  mix  the  alcoholic  solution  with  the  cotton  jelly.  If 
too  thick,  add  more  alcohol.  The  same  may  be  used 
without  the  black,  or  with  other  colors. 

348.  Glazing  Finish. 

I.  Dissolve 

Borax,  3  oz. 

Hot  water,  i  gal. 
Bring  to  a  boil  and  add 

Shellac,  i  Ib. 

Stir  until  dissolved  and  then  add 

Ammonia,      i  tablespoonful  (i  oz.) 
Glycerine,      i  tablespoonful  (i  oz.) 

II.  Dissolve 

Gelatin,  i  Ib.  in 

Hot  water,  i    gal. 

Use  No.  I  alone  or  mixed  with  No.  II. 

349.  Finish  for  Splits.     Prepare  a  60  per   cent  cotton 
solution  from  16  oz.  soluble  cotton  by  using  amyl  acetate. 

First  coat: 

Cotton  solution,        40  per  cent 
Castor  oil,  60  per  cent 

Colored  with  drop  black  and  embossed  either  here  or 
later,  as  desired. 


Second  coat: 


Cotton  solution,        60  per  cent 
Castor  oil,  40  per  cent 


LEATHER  MANUFACTURE  187 

Third  coat: 

Cotton  solution,        70  per  cent 
Castor  oil,  30  per  cent 

350.  Amyl  Acetate  Finish.     Dissolve 

Soluble  cotton,  16  oz.      2\  Ibs. 
Amyl  acetate,  2\  gals. 

Mix  the  above  with  2\  gals,  of  alcohol  and  then  add 
Castor  oil,  i    Ib. 

Dissolve  i  oz.  of  spirit  nigrosine  N  in  J  pt.  of  alcohol 
and  add  to  above.  If  a  dull  foiish  is  desired,  dull  with 
lactic  acid. 

351.  Gray  Ooze.     Run  for  fifteen  minutes  with 

Ferrous  sulphate,      2  per  cent  on  dry  weight 
Wash  for  one-half  hour  and  top  with 

Silver  Gray  G  2  gms.  for  4  skins 

Run  for  fifteen  minutes  and  wash  fifteen  minutes.     Fat 

liquor  with 

Chip  soap,  i    per  cent 

Neatsfoot  oil,  ^  per  cent 

352.  Brown    Ooze.     Mordant   the   stock   with   sumac 
or  quebracho  and  color  with 

Vesuvine  R  3  oz.  per  100  Ibs. 

Flavo-phosphine  G  G  Cone,  i  oz. 
Methylene  Blue,  \  oz. 

353.  Black  Ooze.     Place  the  wet  chrome-tanned  skins 
in  the  drum  and  add 

Logwood  paste,  3  per  cent 

Iron  striker,  i  per  cent 


188      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

Wash  thoroughly  and  fat  liquor  with  a  mixture  of  soap, 
Neatsfoot  oil,  and  soluble  oil,  using  3  per  cent  of  the 
mixture.  Dry  and  buff.  The  burled  skins  are  now  sam- 
mied  and  run  in  the  drum  for  twenty-five  minutes  with 

Logwood,  i^  per  cent 

Fustic,  i    per  cent 

Copperas,  i^  per  cent 

Wash  five  minutes.     For  each  100  Ibs.  add 

Diamond  Green  B  powdered,  3  oz. 
Run  ten  minutes  and  add 

Corvaline  B  T,  i  Ib. 

Vesuvine  V  L  II  3  oz. 

Run  thirty  minutes,  wash,  and  add  2  per  cent  acid  fat 
liquor.  Run  in  fat  liquor  for  thirty  minutes,  hang  up  to 
dry,  dip  in  hot  water,  and  run  in  dry  mill. 

354.  Bronze  Calf  Finish.  Make  lactic  acid  wash  with 
i  pt.  lactic  acid  and  8  pts.  of  water.  Then  dissolve  J 
oz.  Acid  Violet  in  8  oz.  of  denatured  alcohol.  Dis- 
solve \  oz.  fuchsine  crystals  in  8  oz.  of  hot  water.  Mix 
the  Acid  Violet  and  fuchsine  solutions  together  and  add 
a  little  to  the  lactic  acid  wash.  Apply  this  wash  to  the 
skins;  then  make  a  solution  of  \  oz.  of  Acid  Violet  in  8 
oz.  of  alcohol  and  give  one  coat.  Dry  and  glaze;  then 
apply  a  solution  of  J  oz.  fuchsine  and  f  oz.  of  lactic  acid 
in  8  oz.  of  hot  water.  Dry,  glaze,  and  give  coat  of 
finishing  oil. 


CHAPTER  IX 
WOOD   FIBER,   PULP,   AND   PAPER 

355.  On  a  laboratory  scale,  it  is  impossible  to  go  very 
extensively  into  the  manufacture  of  paper  without  en- 
tailing great  expense.     A  few  simple  tests  may  be  per- 
formed, however,   which    will    enable    the    student   more 
fully  to  appreciate  some  of  the  operations  of  this  very 
important  industry. 

Paper  consists  of  cellulose  fibers  matted  or  felted 
together  in  a  sheet.  The  raw  materials  employed  are 
wood  pulp,  cotton  or  linen  rags,  esparto,  straw,  hemp, 
flax,  jute,  etc. 

356.  Wood  Pulp.    As  the  bulk  of  paper  on  the  market 
is  made  entirely  or  in  part  from  wood  fibers,  this  raw 
material  will  be  the  only  one  considered  in  this  chapter. 
For  a  more  detailed  account  of  the  processes  involved 
the   student  is  referred   to   the   "  Manual   of    Industrial 
Chemistry  "  by  the  same  author.     Wood  pulp  is  of  two 
kinds,  mechanical  and  chemical. 

357.  Mechanical  Wood  Pulp.     Mechanical  pulp  may 
be  made  in  the  laboratory  by  forcing  a  stick  of  poplar, 
hemlock,  spruce,  pine,  or  basswood    against    a  revolving 
emery-wheel,  over  which  a  small  stream  of  water  plays 
continuously.     The  resulting  pulp  is  passed  through  sev- 
eral screens  to  remove  insufficiently  disintegrated  particles. 
The  finely  divided  pulp  is  then  brought  into  a  settling 

189 


190      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

tank,  where  it  is  washed,  bleached,  filled,  and  colored 
as  subsequently  described  under  the  treatment  of  chemi- 
cal pulp.  .: .:': 

358.  Chemical  Pulp.  Chemical  pulp  is  prepared  by 
the  soda,  the  sulphite,  or  the  sulphate  processes.  The 
soda  process  is  largely  used  for  soft  woods.  The  bark 
is  removed  by  shaving.  The  wood  is  then  chipped  in 
a  machine,  or  by  hand,  cutting  across  the  grain.  To 
separate  the  knots,  the  chips  are  thrown  into  water,  where 
the  heavy  parts  go  to  the  bottom,  leaving  the  clear  wood 
on  top.  The  digester  is  nearly  filled  with  chips,  which 
are  then  covered  with  a  caustic  liquor  of  about  10°  Be. 
The  cover  of  the  digester  is  safely  screwed  in  place,  and 
the  charge  heated  until  a  pressure  of  90  Ibs.  is  obtained. 
This  pressure  is  held  from  eight  to  ten  hours.  The  effect 
of  this  "  cooking  "  is  to  reduce  the  wood  to  a  soft  mass 
of  grayish-brown  color,  while  the  liquor  becomes  dark 
brown  and  somewhat  increased  in  density.  Now  open 
the  valve  of  the  digester  very  slowly  in  order  to  release 
the  pressure.  Much  care  must  be  taken  here  to  avoid 
any  possibility  of  an  explosion.  If  the  process  has  been 
conducted  properly,  the  stock  will  all  crumble  to  a  pulp, 
which,  together  with  the  "  black  liquor,"  is  transferred 
to  a  suitable  apparatus  and  systematically  washed,  the 
wash  waters  being  saved  until  their  density  falls  below 
8°  Be. 

This  liquor  may  be  evaporated  to  a  density  of  38° 
Be.  and  then  burned.  The  "  black  ash  "  thus  obtained 
may  be  recausticized  with  milk  of  lime,  and  from  80  to 
90  per  cent  'of  the  original  soda  recovered.  The  pulp 
obtained  above  is  thoroughly  washed,  then  passed  through 
a  screen  to  remove  the  larger  particles. 


WOOD   FIBER,  PULP,  AND   PAPER  191 

359.  Bleaching.  The  washed  pulp  is  next  placed  in 
a  vessel  provided  with  some  form  of  agitator  where  it 
is  mixed  with  a  weak  solution  of  calcium  hypochlorite. 
Only  a  clear  solution  of  bleaching  powder  should  be  used, 
so  that  no  dirt  will  be  introduced  into  the  insoluble  res- 
idue, causing  spots  in  the  paper.  If  the  liquid  is  heated 
to  90°  or  100°  F.,  or  a  little  acid  added,  the  process  is 
hastened.  Alum  forms  aluminium  hypochlorites  with 
bleaching  powder  solutions,  which  is  very  effective;  a 
slightly  acid  alum  or  "  bleaching  "  alum  is  commonly 
employed.  From  18  to  25  parts  of  bleaching  powder 
is  used  for  each  100  parts  of  pulp.  As  soon  ,as  bleached, 
the  process  is  stopped,  otherwise  the  fiber  is  apt  to  be 
chlorinated,  and  color  again  taken  up.  The  excess  of 
hypochlorite  in  the  pulp  is  washed  out  with  water,  or  is 
destroyed  by  adding  an  antichlor,  such  as  sodium  thio- 
sulphate.  The  action  of  the  antichlor  is  as  follows: 


The  pulp  must  be  thoroughly  washed  after  bleaching, 
even  when  antichlors  are  used,  since  injurious  substances 
may  be  left  in  the  pulp. 

Other  materials  than  bleaching  powder,  such  as  ozone, 
hydrogen  peroxide,  sulphurous  acid,  liquid  chlorine,  or 
sodium  peroxide,  have  been  suggested  for  bleaching,  but 
as  yet  the  hypochlorites  are  most  common. 

360.  The  Paper  Making  Process.  The  first  operation 
is  "  furnishing  "  or  "  charging  "  the  stock;  the  kinds  and 
quantity  of  material  employed  depend  on  the  quality  of 
the  paper  to  be  produced.  In  order  to  give  the  paper 
body,  weight,  and  greater  smoothness,  mineral  filler  or 
"  loading  "  material  is  used.  This  must  be  exceedingly 


192      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

fine,  not  too  high  in  specific  gravity,  and  insoluble 
in  water.  It  must  be  free  from  dirt,  grit,  and  mica. 
The  loading  is  done  after  the  fiber  has  been  well  beaten 
with  water.  The  filler  is  thoroughly  mixed  with  pulp, 
then  the  sizing  material  added,  and  the  whole  beaten 
until  a  perfect  mixture  of  all  the  materials  is  obtained. 
Some  of  the  fillers  adapted  to  paper  making  are  clay, 
chalk,  and  calcium  sulphate;  while  a  good  size  may  be 
prepared  from  rosin  with  a  concentrated  solution  of  soda 
ash.  The  proportion  of  filler  and  size  varies  within  quite 
a  wide  range;  good  results,  however,  may  be  secured 
with  5  per  cent  of  filler  and  3  per  cent  of  size  on  the  weight 
of  the  moist  pulp.  After  the  pulp,  filler,  and  size  have 
been  well  beaten,  a  solution  of  aluminium  sulphate  is 
added  in  sufficient  quantity  to  neutralize  the  soda  of  the 
rosin  soap.  The  result  of  this  treatment  is  to  form  free 
rosin  and  some  aluminium  hydroxide,  which  becomes 
entangled  in  the  openings  between  the  fibers.  Paper  is 
usually  colored  by  adding  pigments  or  dyes  to  the  pulp. 
For  white  paper,  the  slight  yellow  tinge  of  bleached  fiber 
is  neutralized  with  a  trace  of  blue  or  pink,  ultramarine 
or  coal-tar  dyes  being  used.  Some  pigments  are  pre- 
cipitated in  the  fiber  by  adding  solutions  in  the  hollander. 

The  sheet  is  formed  in  three  different  ways,  viz.,  by 
the  hand  frame,  the  cylinder  machine,  and  the  Fourdrinicr 
machine. 

361.  The  Hand  Frame.  For  laboratory  work  the  hand 
frame  may  be  employed.  It  is  simply  a  rectangular  frame 
covered  with  wire  gauze  and  having  a  slight  removable 
ledge  around  the  sides.  The  frame  is  submerged  in  the 
pulp,  mixed  to  a  thin  cream  with  water;  when  raised, 
the  ledge  retains  some  of  the  pulp  on  the  gauze,  while 


WOOD   FIBER,   PULP,  AND  PAPER  193 

the  water  drains  through.  At  the  same  time,  the  frame 
is  slightly  shaken  from  side  to  side,  causing  the  fibers  to 
"  felt  "  and  form  a  mat  of  pulp  on  the  gauze.  The  frame 
is  then  inverted  over  a  woolen  felt  blanket  on  which  the 
sheet  of  pulp  drops.  A  number  of  these  pieces  of  felt, 
each  carrying  a  sheet  of  pulp,  are  piled,  one  above  the  other 
other  and  heavily  pressed  until  the  water  is  expelled. 
The  sheets  are  then  dipped  into  a  fairly  strong  solution 
of  glue  or  gelatin  and  allowed  to  dry  slowly. 

The  dried  sheet  is  run  between  a  hot  roller  to 
produce  a  final  finish.  A  common  photographic  burnisher 
will  answer  the  purpose  very  well,  it  simply  being  neces- 
sary to  have  two  polished  rolls  in  place  of  the  usual  machine 
with  only  one  polished  roll. 

362.  Rosin  Size.     Into  an  iron  kettle  place  700  cc.  of 
water  and  dissolve  in  this  20  gms.  of  soda  ash.     Bring  to 
a  boil  and  slowly  add  150  gms.  of  powdered  rosin.     A 
large  amount  of  carbon  dioxide  is  generated,  consequently 
the  kettle  should  be  of  sufficient  capacity  to  prevent  the 
liquid  from  going  over  the  side.     In  order  to  avoid  too 
great  a  loss  by  evaporation,  water  is  added  from  time  to 
tune,  the  level  being  regulated  by  means  of  a  stick  with 
a  notch  cut  at  the  original  height  of  the  liquid.     When 
all  of  the  rosin  has  dissolved,  the  mixture  is  allowed  to 
cool  and  is  practically  a   25  per  cent  solution  of  rosin 
soap.     A  stronger  size  may  be  made  by  using  less  water. 

Casein  Size.  This  size  is  prepared  by  dissolving  casein 
in  cold  soda  ash  (5  to  i)  or  borax  solution.  It  is  applied 
in  the  same  manner  as  that  given  for  rosin  size. 

363.  Colored    Paper.     Pulp    colors   may  be  added  to 
the  pulp  in  the  beater  in  any  amount  desired  to  produce 
the   required   shade.     Very  often,   however,   the  color  is 


194      LABORATORY  GUIDE  OF  INDUSTRIAL   CHEMISTRY 

produced  by  direct  application  of  coal-tar  dyes,  the 
general  method  of  procedure  being  as  follows: 

The  pulp  and  filler  are  introduced  into  the  pulping 
machine  and  well  worked.  The  requisite  amount  of  color 
previously  dissolved  in  water  is  now  added,  worked  in 
thoroughly,  and  then  followed  by  the  rosin  size  and 
alum.  The  well-beaten  mass  is  then  formed  into  sheets 
and  treated  as  above. 

To  produce  light  shades,  |  per  cent  of  color  on  the 
weight  of  the  dry  pulp  is  used;  for  medium  shades,  i 
per  cent;  for  heavy  shades,  as  much  as  3  per  cent. 

The  dyestuffs  used  for  coloring  pulp  may  be  any  acid 
color,  or  direct  cotton  color.  Other  colors  will  require  fix- 
ing agents. 

The  following  list  of  colors  may  be  found  of  service: 

Uranine  O,  soluble  Dianil  Red 

Eosine,  all  brands  Dianil  Scarlet 

Erythrosine,  all  brands  Dianil  Blue 

Acid  Violet,  all  brands  Dianil  Brown 

Naphthol  Yellow,  all  brands  Dianil  Black 
Orange,  all  brands  Direct  Black 


CHAPTER  X 
USEFUL  DATA 

364.  Thermometer  Conversion.     In  order  to  convert 
centigrade    (Celsius)    into     Fahrenheit    (above    freezing- 
point),  multiply  by  9,  divide  the  product  by  5,  and  add 
32  to  the  quotient. 

To  convert  Fahrenheit  above  freezing-point  into  centi- 
grade, subtract  32,  multiply  the  remainder  by  5,  and 
divide  the  product  by  9. 

To  convert  Reaumur  into  Fahrenheit,  multiply  by  9, 
divide  by  4,  and  add  32  to  the  quotient. 

To  convert  Fahrenheit  into  Reaumur,  subtract  32, 
multiply  the  remainder  by  4,  and  divide  the  product  by  9. 

365.  Mensuration   of   Volume.     The   standard   gallon 
measures  231  cu.  ins.  and  weighs  8.338  Ibs. 

One  cubic  foot  contains  7.4805  gals,  and  weighs  998.8 
oz.  or  62.425  Ibs. 

To  facilitate  computation,  the  weight  of  a  cubic  foot 
of  water  is  usually  taken  as  1000  oz.  or  62.5  Ibs. 

Water  expands  from  40°  to  202°  to  the  amount  of 
.0467  per  cent  or  .002715  per  cent  for  each  degree,  giving 
an  increase  of  i  cu.  ft.  in  21.41  cu.  ft. 

366.  To  Compute  Volume  of  a  Cube.     Multiply  a  side 
of  a  cube  by  itself  and  that  product  again  by  a  side. 

367.  To  Compute  Volume  of  a  Parallelopipedon.     Mul- 
tiply length  by  breadth  and  that  product  again  by  depth. 

195 


196      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 


368.  To  Compute  Volume  of  a  Cylinder.  Multiply 
area  of  base  by  height. 

Example.  Diameter  of  a  cylinder  is  3  ft.  and  its 
height  is  7  ft.;  what  is  the  volume? 

First,  to  get  the  area  of  base,  multiply  the  square  of 
the  diameter  by  .7854,  then  this  product  by  the  height: 

3  X3X. 7854  =  7-o68 
7.068X7  =  49.476  cubic  feet 

If  it  is  desired  to  know  the  contents  in  gallons,  then 
49.476X7.4805=370.1  gallons. 

369.  HYDROMETER  SCALE   SHOWING   RELATIONS 
OF  SPECIFIC  GRAVITY,  BAUME,  AND  TWADDELL. 


Specific 
Gravity 

Degrees 
Baume 

Degrees 
Twaddell 

Specific 
Gravity 

Degrees 
Baume 

Degrees 
Twaddell 

Specific 
Gravity 

Degrees 
Baume 

Degrees 
Twaddell 

I.OOO 

O 

.O 

1  80 

22 

36.0 

1.440 

44 

88.0 

1.007 

I 

1-4 

I  QO 

23 

38.0 

1-454 

45 

90.8 

OI4 

2 

2.8 

199 

24 

39-o 

1.470 

46 

94-0 

022 

3 

4-4 

2IO 

25 

42.0 

1-485 

47 

97-0 

029 

4 

5-8 

221 

26 

44-2 

1.501 

48 

IOO.  2 

036 

5 

7-2 

.231 

27 

46.2 

1.576 

49 

103.2 

.044 

6 

8.8 

.242 

28 

48.4 

1-532 

50 

106.4 

.052 

7 

10.4 

.252 

29 

50-4 

1-545 

5i 

109.2 

.060 

8 

12.0 

.261 

30 

52.2 

1.560 

52 

112.  6 

.067 

9 

13-4 

•275 

31 

55-0 

1.580 

53 

116.0 

•075 

10 

IS-0 

.286 

32 

57-2 

1-595 

54 

119.4 

-083 

ii 

16.6 

.298 

33 

59-6 

1.615 

55 

123.0 

.OQI 

12 

18.2 

.309 

34 

61.8 

1-635 

56 

127.0 

.100 

13 

20.  o 

.321 

35 

64.  2 

1-650 

57 

130.4 

.108 

14 

21.6 

•334 

36 

66.8 

1.670 

58 

134-4 

.116 

15 

23.2 

.346 

37 

69.2 

1.690 

59 

138-2 

•  125 

16 

25.0 

•359 

38 

71.8 

i  .  710 

60 

142.0 

.134 

17 

26.8 

•372 

39 

74-4 

1.730 

61 

146.4 

.143 

18 

28.6 

.384 

40 

76.8 

1-750 

62 

150.6 

.152 

iQ 

30-4 

.398 

4i 

79.6 

1-775 

63 

155-0 

1.161 

20 

32.2 

.412 

42 

82.4 

1-795 

64 

159-0 

1.171 

21 

34.2 

.426 

43 

85.2 

1.820 

65 

164.0 

USEFUL  DATA  197 

370.  To  Compute  Volume  of  a  Cone.    Multiply  the 
area  of  the  base  by  perpendicular  height,  and  take  one- 
third  of  product. 

371.  To  Compute  Volume  of  a  Frustum  of  a  Cone. 

Add  together  square  of  the  diameters  of  greater  and 
lesser  sides  and  product  of  the  two  diameters;  multiply 
the  sum.  by  .7854  and  this  product  by  height;  then 
divide  the  last  product  by  3. 

Example.  What  is  the  volume  of  frustum  of  a  cone, 
diameter  of  greater  and  lesser  ends  being  5  and  3  ft.,  and 
height  9  feet. 

52+32+(5X3)=49 
49  X. 7854  =  38.4846 

38.4846X9  - 
-  =  115.453801.  ft. 

3 

372.  To  Compute  Volume  of   Sphere.     Multiply  the 
cube  of  the  diameter  by  .5236. 

Example.  What  is  the  volume  of  a  sphere,  the  diam- 
eter being  10  ins.? 

io3  =  1000  and  1000 X. 5236  =  523.6  cu.  ins. 

This  rule  will  apply  to  the  measurement  of  kettles 
which,  as  a  rule,  are  one-half  a  sphere. 

If  the  kettle  is  a  combination  of  a  sphere  and  cylinder, 
the  measurement  of  each  may  be  made  and  the  contents 
thus  determined.  In  all  of  the  above  measurements  it 
is  a  simple  matter  to  ascertain  the  number  of  pounds  by 
multiplying  the  number  of  cubic  feet  by  62.425  and  then 
by  the  specific  gravity  of  the  substance  in  question. 


198      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 


373.  The  weight  per  cubic  foot  of  a  few  common  sub- 
stances as  indicated  in  the  following  table,  may  be  found 
useful: 

374.    SOLIDS 


Substance 

Weight 
per 
Cu.  Ft. 

Substance 

Weight 
per 
Cu.  Ft. 

Substance 

Weight 
per 
Cu.  Ft. 

Charcoal  .... 

27-5 

Cannel  

82.3 

Magnesia.  .  .  . 

ISO. 

Alum  

107. 

Coke  

62.5 

Magnetic  ore. 

3176 

Asbestos.  .  .  . 

IQ2. 

Concrete  .... 

137-5 

Marble  

165. 

Asphalt 

140  6 

Earth,  dry. 

Mud. 

IOI 

Borax  

107. 

soil.  .  . 

76.0 

Quartz  

166  25 

Brick  

I^O. 

"  loose   . 

03   7 

Red  lead    . 

558  7 

Cement, 

"  moist  sand 

120. 

Ro  stone  .... 

123.8 

Portland.  . 

81.25 

Granite  

165. 

Salt  

133- 

Clay.    . 

1  20  6 

Gravel 

1^7    r 

Sand.  .  :  .  . 

112 

Coal  

Gypsum  

135.5 

Sulphur  

127. 

Anthracite.  .  . 

84  to  102.5 

Lime  

50.25 

Pumice-stone 

57- 

Caking  

79-8 

Limestone  .  . 

197-25 

• 

375.   LIQUIDS  AND   SEMI-SOLIDS 


Substance 

Weight 
in  Ibs. 
per 
Cu.  Ft. 

Substance 

Weight 
in  Ibs. 
per 
Cu.  Ft. 

1 
Substance 

Weight 
in  Ibs. 
per 
Cu.  Ft. 

Acid,  acetic  
"  Sulphuric 

66.3 

II1?       ^ 

Butter  
Cotton.  .  . 

58.8 
trn    -2 

Milk  
Oil,  linseed 

64.5 
e8  7 

"Hydrochloric. 
"Nitric  
Alcohol  95%. 

75- 
70. 
crj 

Glycerin  60°  . 
Ice  
Lard.  . 

78.7 

57-5 

CO 

Petroleum.  .  . 
Resin  
Starch    .  .    .  . 

55- 
68. 

CQ 

Ammonia 

Leather 

60 

Sugar 

IOO     T, 

27-9%... 

55-6 

Tallow  

58.8 

To  compute  the  weight  of  a  body  in  pounds  per  cubic  foot,  divide  the 
specific  gravity  by  16. 


USEFUL  DATA  199 

376.  To  Compute  Pressure  of  a  Fluid  upon  Bottom  of 
its  Containing  Vessel.     Multiply  area  of  base  by  height 
of  fluid  in  feet,  and  product  by  weight  of  a  cubic  foot 
of  fluid. 

377.  To  Compute  Pressure  of  a  Fluid  upon  a  Vertical, 
Inclined,  or  Any  Surface.     Multiply  area  of  surface  by 
height  of  center  of  gravity  of  fluid  in  feet,  and  product 
by  weight  of  cubic  foot  of  fluid. 

Example.    What  is  pressure  upon  a  sloping  side  of  a 
pond  of  fresh  water  10  ft.  square  and  8  ft.  in  depth? 
Center  of  gravity  8-^2=4  feet  from  surface. 
Then  io2X4X62.5  =  25,ooo  Ibs. 

378.  Equivalents  of  Metric  Weights  and  Measures 

i  pound  =453-59  gms. 

i  oz.  avoirdupois  =  28.349  gms. 

i  U.  S.  gallon  =3-785  liters 

i  U.  S.  liquid  oz.  =29.574  cc. 

Grains  per  imperial  gallon 

—  =  parts  per  100,000. 

Parts  per  100,000X0.7      =  grains  per  imperial  gal. 

Grains  per  U.  S.  gallon 

—  =  parts  per  100,000. 

Parts  per  100,000 X. 583    =  grains  per  U.  S.  gallon. 

379.  Table  of  Multiples. 
Centimeters  X  0.393 7=  inches. 
Cen  timetersX  0.03  28  =  feet. 

Centimeters  cubic  X 0.0338  =  apothecaries'  fluid  ounces. 

Diameter  of  a  circle X 3. 1416  =  circumference. 

U.  S.  gallons X 3. 785  =  liters. 

U.  S.  Gallons  X 0.833 56 5=  imperial  gallons. 

Gallons,  imperial  X  1.199666  =  11.  S.  gallons. 


200      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 

U.  S.  gallons  X 8. 33505=  pounds  of  water. 
Gallons,  imperial  Xio= pounds  of  water. 
Gallons,  imperial  X4-54io2=  liters. 
Grains  X  0.0648  =  grams. 
Inches  X  0.0254  =  meters. 
Inches  X  25.4  =  millimeters. 
Miles  X  i  .609  =  kilometers. 
Ounces,  troy  X  i  .907  =  ounces  avoirdupois. 
Ounces  avoirdupois Xo.9i  15 Bounces  troy. 
Pounds  avoirdupois  X  0.453 6  =  kilograms. 
Pounds  avoirdupois  Xo.8228572  =  pounds  troy. 
Pounds  troy  X 0.3 7 286  =  kilograms. 
Pounds  troy  X i. 2 1 52 7=  pounds  avoirdupois. 
The  square  of  the  circumference  of  a  circle  X 0.07958 
=  area. 

380.  Board  and  Timber  Measure.     In  board  measure 
all  boards  are  assumed  to  be  i  inch  in  thickness. 

381.  To  Compute  the  Measure  of  Surface.    When  all 
dimensions  are  in  feet,  multiply  length  by  breadth  and 
product  will  give  surface  in  square  feet. 

When  either  of  dimension  is  in  inches  divide  the  product 
by  12. 

Example.  What  is  number  of  square  feet  in  a  board 
15  ft.  long  by  1 6  ins.  wide? 

15X16  =  240,  and  240-1-12  =  20  sq.ft. 

382.  To  Compute  Volume  of  Round  Timber.    When  all 
dimensions  are  in  feet,  add  together  squares  of  diameters 
of  greater  and  lesser  sides  and  products  of  the  two  diam- 
eters;   multiply  sum  by  .7854  and  product  by  one- third 
of  length. 


USEFUL  DATA 


201 


When  the  length  is  in  feet  and  diameter  in  inches, 
proceed  as  above,  but  divide  by  144. 

If  surface  or  board  measure  is  desired,  multiply  volume 
by  12. 

383.  UNITS  FOR  COMPUTING  SAFE  STRAIN  THAT 
MAY  BE  BORNE  BY  NEW  ROPES,  HAWSERS, 
AND  CABLES. 


ROPES 

HAWSERS 

CABLES 

Descrip- 

Circum- 
ference 

White 

Tarred 

White 

Tarred 

White 

Tarred 

Ins. 

3 

4 

3 

4 

3 

3 

3 

3 

Strands 

Strands 

Strands 

Strands 

Strands 

Strands 

Strands 

Strands 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

White 

2-5-  6 

1140 

1330 

— 

— 

600 

— 

— 

— 

<  < 

6-8 

IOQO 

1260 

— 

— 

570 

— 

510 

— 

<  < 

8    -12 

1045 

880 

— 

— 

55° 

— 

53° 

— 

<  « 

12    -18 

— 

— 

— 

— 

550 

— 

550 

— 

«  < 

18    -26 

— 

— 

— 

— 

— 

— 

560 

— 

Tarred 

2.5-5 

— 

— 

855 

1005 

— 

460 

— 

— 

<  < 

5    -8 

— 

— 

825 

940 

— 

480 

— 

— 

i  ( 

8    -12 

— 

— 

780 

820 

— 

505 

— 

— 

« 

12     -18 

— 

— 

— 

— 

— 

— 

— 

505 

<  t 

18    -26 

— 

— 

— 

— 

— 

— 

— 

525 

Manilla 

2.5-6 

810 

950 

— 

— 

440 

— 

— 

550 

<  < 

6    -12 

760 

835 

— 

— 

465 

— 

5io 

— 

<  < 

12     -18 

— 

— 

— 

— 

— 

— 

535 

— 

<  i 

18    -26 

— 

— 

— 

— 

— 

— 

56o 

— 

Illustration.  What  weight  can  be  borne  with  safety 
by  a  manilla  rope  of  3  strands  having  a  circumference  of 
6  inches? 


Ibs. 


202      LABORATORY  GUIDE  OF  INDUSTRIAL  CHEMISTRY 


384.     WEIGHTS.     EVAPORATIVE  POWER  PER 
WEIGHT  AND  BULK  OF  DIFFERENT  FUELS 


£ 

|a 

£ 

£ 

I- 

H 

Fuel, 

o 

*  . 

M 

Fuel, 

u 

C  -C     * 

d 

Bituminous 

& 

!°jj 

C 

Anthracite 

fc 

a 

c 

.fl  w 

W.O 

g  ^i 

^  0 

-C  oi 

g  «TJ 

£  ^ 

•83 

<y  ctf  PH 

jj£ 

'Si-5 

S  "Sft, 

tf 

* 

« 

0 

^ 

• 

0 

Cumberland,  max. 

52.92 

10.7 

42.3 

Peach  Mountain.  . 

52.79 

IO.  II 

41.6 

min. 

54-29 

9-44 

41.2 

Forest  Improve..  . 

53-66 

10.  06 

41-7 

Duflfryn 

53-22 

10.14 

42.09 

Beaver  Meadow.  . 

56.19 

9.88 

39-8 

Cannel,  Wigan.  .  . 

48.3 

7-  7 

46.  37 

Lacka  wanna. 

48  89 

0    70 

45-8 

Blossburgh  ...    . 

T-W     ^ 

c?   cx 

o  72 

42.  2 

Lehigh  

*TW  *  wy 

6=;  32 

y  -  /  y 

o 

Newcastle 

oo  •    o 
so  82 

y  -  / 
8  76 

44 

COKE 

0  •  O 

' 

' 

Pittsburg  

0     • 

46.81 

***/** 

8.2 

47.8 

Natural  Virginia.  . 

46.  64 

8.47 

48    3 

Sydney  

47   44 

7   99 

47-  2 

Cumberland 

31.6 

8  oo 

V  •  o 

70.9 

Clover  Hill,  Va... 

*T  /    '  T-T- 

45-49 

/   yy 
7-67 

49-2 

MISCELLANEOUS 

*  y  v 

Cannelton,  Ind.  .  . 

47-65 

7-34 

47 

Charcoal,  Oak  .  .  . 

24- 

5-5 

IO4 

Scotch  

51  -°9 

7.08 

43.8 

Peat  

30 

r 

7  ^ 

T"O 

Pine  Wood  

o 

21. 

0 

4-7 

/  j 

106.6 

385.  FRIGORIFIC  MIXTURES. 


Mixtures 

Parts 

Fall  of 
Temperature 

Mixture 

Parts 

Fall  of 
Temperature 

Sea  salt  

C  ) 

Snow  

I  } 

Ammonium  nitrate 

Calcium 

-4o0to-73° 

Snow  or 

( 

-15  10-25 

chloride  .  . 

3! 

powdered  ice.  .  . 

I2J 

Ammonium 

Snow  

81 

chloride  

5) 

Dilute  sul- 

-68°to-9i° 

Snow  or 

-  5°to-i8° 

phuric  acid 

10  J 

powdered  ice.  .  . 

oJ 

'  ,.    • 

USEFUL  DATA 


203 


386.  INTERNATIONAL   ATOMIC   WEIGHTS,   1917. 


Sym 
bol. 

Atomic 
weight. 

Sym- 
bol. 

Atomic 
weight. 

Aluminium 

A1 

27.  I 

Molybdenum  

Mo 

96.0 

Antimony          •    ' 

Sb 

1  2O    2 

Neodymium  

Nd 

144   ? 

A 

30  88 

Neon 

NP 

2O   2 

Arsenic 

As 

74  06 

Nickel  

Ni 

58.68 

Barium                   .  .  . 

En 

137.  37 

Niton  (radium  emanation) 

Nt 

222.4 

Bismuth 

Bi 

208  o 

Nitrogen  

N 

14.01 

Boron 

ft 

II    O 

Osmium  

Os 

IOO    O 

Br 

7O    O2 

Oxygen 

O 

1  6  oo 

Cadmium 

Td 

112    40 

Palladium  

Pd 

106  7 

Cs 

132  81 

Phosphorus 

P 

31    O4. 

Calcium 

Pa 

4.O   O7 

Platinum  

Pt 

IO^    2 

Carbon 

c 

1  2    OO5 

Potassium 

K 

30    IO 

Cerium 

TP 

I4.O    2^ 

Praseodymium  

Pr 

140.  o 

Chlorine 

n 

2C    4.6 

Radium             

Ra 

226  o 

o 

r  2    O 

Rhodium 

Ph 

IO2    Q 

Cobalt 

To 

cr8    07 

Rubidium  

Pb 

8q  4"? 

Columbium 

rb 

Q-J      I 

Ruthenium 

Rn 

IOI    7 

CoDDer 

Oi 

63    s?7 

Samarium  

Sa 

1^04 

Dysprosium 

Dy 

162  5 

Scandium 

Sr 

44    I 

Erbium 

Fr 

167   7 

Selenium  

SP 

70   2 

Europium 

Fu 

I  C2    O 

Silicon 

Si 

28    3 

Fluorine 

F 

IO    O 

Silver  

Ag 

107.88 

Gadolinium 

Gd 

icy    -i 

Sodium   .  .           

Na 

23    OO 

Gallium 

Ga 

60  o 

Strontium  

Sr 

87.63 

Germanium 

GP 

72    <C 

Sulphur     

S 

^2       O6 

Glucinum  

G1 

O.  I 

Tantalum  

Ta 

iSl.S 

Gold. 

An 

107    2 

Tellurium  

TP 

127    ^ 

Helium 

HP 

4OO 

Terbium 

Tb 

irn    2 

Holmium.  . 

Ho 

163  5 

Thallium  

Tl 

204  o 

Hydrogen 

H 

i  008 

Thorium  

Th 

2^2    4 

Indium 

In 

114.   8 

Thulium 

Tm 

168  t: 

Iodine 

T 

126    02 

Tin  

Sn 

118  7 

Iridium 

Tr 

JQ-7      I 

Titanium. 

Ti 

48  i 

Iron  ...            ... 

FP 

cc   84 

Tungsten  

W 

184.0 

Krypton 

Kr 

82  92 

Uranium 

TT 

238    2 

Lanthanum  

La 

1  30   O 

Vanadium  

V 

t;i  .0 

Lead. 

Pb 

2O7    2O 

Xenon                          .    . 

XP 

3O    2 

Lithium  

Li 

6  04 

Ytterbium  (Neoytterbium) 

Yb 

73-5 

Lutecium 

T,n- 

7:;   o 

Yttrium  

Yt 

88.7 

M^agnesium 

Ms 

24.    32 

Zinc 

7n 

6^    37 

Manganese           .    . 

Mn 

CA     Q? 

Zirconium  

7,r 

90.6 

Mercury  

Hg 

00.6 

204      LABORATORY   GUIDE  OF  INDUSTRIAL   CHEMISTRY 

387.  Speed  of  Pulleys. 

V  and  v  speed  of  driving  and  driven  pulleys. 
D  and  d  diameter  of  driving  and  driven  pulleys. 
R  and  r  number  of  revolutions. 

dr     ,     DR  dr         DR 


In  a  train  of  pulleys  the  final  velocity 

V=  VD,  D',  D",  etc.-K  d',  d",  etc. 

388.  Unit  of  Electrical  Resistance.     The  ohm  is  repre- 
sented by  the  resistance  offered  at  o°  C.  to  an  unvarying 
electric  current  by  a  column  of  mercury  14.4521  gms.  in 
mass,  of  a  constant  cross-sectional  area,  and  of  a  length 
of  106.3  centimeters. 

389.  Unit  of  Current.     The  ampere  is  an  unvarying 
current  passing   through   a   solution   of  silver  nitrate  in 
water  and  deposited  at  the  rate  of  .001118  gm.  per  second. 

390.  Unit  of  Electro-motive   Force.     The   wit  is   the 
pressure  which,  if  steadily  applied  to  a  conductor  having 
the  resistance  of  one  ohm,  will  produce  a  current  of  i  ampere. 

391.  Unit  of  Quantity.     The  coulomb  is  the  quantity 
of  electricity  transferred  by  a  current  of  i  ampere  in  i 
second. 

392.  Unit  of  Capacity.    The  farad  is  the  capacity  of  a 
condenser  charged  to  a  potential  of  i  volt  by  i  coulomb 
of  electricity. 

393.  Unit  of  Work.     The  joule  is  equal  to  io7  units  of 
work  in  the  C.  G.  S.  system  and  is  practically  equivalent  to 
the  energy  expended  in  one  second  by  an  ampere  in  an  ohm. 

394.  Unit  of  Power.     The  watt,  is  equivalent  to  the 
work  done  by  i  joule  in  one  second. 


INDEX 


Acetamide,  55 
Acetanilide,  77 
Acetic  acid,  50 
Acetic  anhydride,  52 
Acetone,  47 
Acetyl  chloride,  51 
Acid,  acetic,  50 

anthraquinone  sulphonic,  88 

benzoic,  65 

cinnamic,  72 

monochloracetic,  54 

naphthalene  sulphonic  j8,  81 

naphthol-6-sulphonic  /3,  83 

naphthol-3 :  6-disulphonic  /3,  84 

picric,  71 

salicylic,  73 

succinic,  57 

/>-sulphanilic,  76 
Acid  colors  for  lakes,  214 
Acid    colors    on    chrome-tanned 

leather,  324 
Acid  dyes,  124,  125 
Acid  hemlock  sole,  332 
Alcohol,  44 

ethyl,  44 
Alizarine,  94 

dyes,  123 

lakes,  223 
Alum  mordant,  117 

potash,  24 

tannage,  330 


Aluminium  sulphate,  23     - 
Ammonium  paratungstate,  42 
Ampere,  389 
Amyl  acetate,  53,  350 
Aniline,  74 
Anisol,  64 
Anthraquinone,  87 
Anthraquinone  sulphonic  acid,  88 
Antimony  vermilion,  193 
Atomic  weights,  386 

Balance,  Westphal,  22 
Barium  carbonate,  25 

chloride,  25 

peroxide,  28 
Barkometer,  18 
Barytes,  25 

Basic  colors  for  lakes,  208 
Basis  dyes,  106,  125 
Bate,  ammonium  chloride,  314  (e) 
Bating,  314,  317 
Baume's  hydrometer,  20 
Bauxite,  23 
Benzaldehyde,  63 
Benzidine,  80 
Benzoic  acid,  65 
Benzoyl  chloride,  67 
Benzyl  chloride,  62 
Black  ash,  358 
Black  ooze,  353 
Blue  lake,  210 


205 


206 


INDEX 


Board  measure,  380 

Body  varnish,  253 

Boiled  soap,  303 

Bone  ash,  37 

Bordeaux  B,  99 

Bottle,  specific  gravity,  16,  21 

Brilliant  finish,  345 

Bronze  finish,  354 

Brown  hard  spirit  varnish,  248 

Brown  lake,  212 

Brown  ooze,  352 

Brunswick  green,  201,  202,  203, 

204,  205 

Buckskin  leather,  331 
Buhr  stone  mill,  260 
Burnishing,  360 

Calcination,  8 
Calf  leather,  318 
Campeachy  wood,  114 
Carbolic  acid,  60 
Casein  size,  362 
Centrifuge,  13 
Chemical  pulp,  358 
Chloroform,  49 
Chrome,  dark  tan,  323 

green,  200 

mordant,  118 

one-bath,  317  (b) 

orange,  197 

red,  196 

two-bath,  316 

yellow,  195 
Chromite,  27 
Chromium  acetate,  26 
Chrysamine  G,  100 
Cinnamic  acid,  72 
Coach  oils,  238,  239,  240 


Coach,  varnish,  255 
Cold-made  soap,  294 
f    Collodion  varnish,  251 
Colored  paper,  363 
Colors,  harmony  of,  327 
,        letters  on,  326 

mixing  of,  328 

primary,  326 

secondary,  326 

shades  of,  329 

spirit,  in 
Concentration,  16 
Cone,  volume  of,  370 
Cost  system,  23 
Cotton,  131 

dyeing  of,  132,  133 

printing,  188 

finish,  347 

Turkey  Red  on,  178 
Coulomb,  391 
Crimson  lake,  207,  211 

red,  225 
Crusher,  jaw,  i 
Crushing,  i 
Crutcher,  294 
Crystallization,  9 
Cube,  volume  of,  366 
Cylinder,  volume  of.  368 

Dammar  varnish,  250 

Dark  tan  chrome,  323 

Decantation,  4 

Density,  16 

Depilating,  313,  317  (6),  318 

calcium  chloride  process,  313(0 

lime  process,  313  (a) 

painting,  313  (d) 

sulphide  process,  313  (b) 


INDEX 


207 


Developed  dyes,  no,  166 

Diazo  dyes,  166 

Dimethyl  aniline,  75 

Dinitrosoresorcine,  91 

Direct  colors  on  chrome-tanned 

leather,  324 
Disodium   hydrogen   phosphate, 

37 

Distillation,  fractional,  15 
Dog  soap,  302 
Driers,  227 

Japan,  237 

Linseed  oil,  234 

No.  i,  heavy,  235 

No.  2,  236 
Drying,  13 
Drying  oven,  13 
Dyeing,  102 

cold,  145 

instructions  for,  112 
Dyes,  acid,  105,  124 

alizarine,  123 

basic,  106,  125 

developed,  no,  166 

diazo,  167 

cosine,  107 

fastness  of,  138,  139,  140,  141 

monogenetic,  118 

mordant,  109 

poly  genetic,  118 

substantive,  108 

Elastic  varnish,  254,  256 
Electrical  capacity,  unit  of,  392 

current,  unit  of,  389 

power,  unit  of,  391 

quantity,  unit  of,  391 
Electrical  resistance,  unit  of,  388 


Electrical  work,  unit  of,  393 
Electromotive  force,  unit  of,  390 
Enamels,  292 
Eosine,  90 
Eosine  dyes,  107 
Ether,  46 

ethyl,  46 
Ethyl  alcohol,  44 

bromide,  45 

ether,  46 

Ethylene  bromide,  56 
Evaporating  power  of  fuels,  384 
Evaporation,    by  indirect   heat, 

r(f) 

by  direct  heat,  7  (b) 

under  reduced  pressure,  7  (d) 

spontaneous,  7  (a) 

Farad,  392 

Fast   brown   on    chrome-tanned 

calf,  325 

Fast  brown  on  side  leather,  325 
Fast  Green  O,  91 
Fast  Red  B,  99 
Fastness  of  dyes,  138,    139,    140, 

141 

Fat  liquoring,  317 
Ferric  sulphate,  31 
Ferrous  ammonium  sulphate,  30 
Ferrous  sulphate,  29 
Filler,  284,  285 
Filter  bag,  10 

paper,  10 

press,  12 

vacuum,  n 
Finish  for  splits,  349 
Flesher,  312 
Fleshing,  317  (6) 


208 


INDEX 


Flint  hides,  312 
Fluorescein,  89 
French  polish,  244 
French  varnish,  247 
Frigorific  mixtures,  385 
Frustum  of  a  cone,  volume  of, 

37i 

Fuels,  evaporating  power  of,  384 
Furnace,  muffle,  8 

reverberatory,  8 

revolving,  8 

Glaze  finish,  322,  342,  346,  348 

Glazed  goat,  319 

Gray  ooze,  351 

Green  castile  soap,  295,  299 

Grinding,  2 

Gun  metal  finish,  341,  342 

Half-boiled  soap,  297 
Hand  frame,  361 
Harmony  of  colors,  327 
Heavy  drier,  No.  i,  235 
Hides,  flint,  312 
Hydrogen  peroxide,  28 
Hydrometer,  16 

Baume's,  20 

Direct  specific -gravity,  17 

Scales,  369 

Twaddell's,  19 
Hydrosulphite  vat,  176 

Indigo,  174,  175,  176,  177 

Indulin,  96 

lodoform,  48 

Iron  sulphate  vat,  175 

Japan  drier,  237 


Japanning  kid,  335 
Joule,  393 

Kettle,  steam-jacketed,  7 

Lakes,  206 

acid  colors  for,  214 
basic  colors  for,  208 
on  lead  salts,  224 

Laundry  soap,  296,  301 

Lead  borate,  228 
linoleate,  230 
nitrate,  32 
resinate,  232 

Leather,  buckskin,  331 
calf,  318 

coloring  of,  316,  317 
degreasing,  316 
finishing  of,  316,  317 
glaze  finish,  316  (a) 
mat  finish,  316  (b) 
neutralizing,  317 
side,  318 

Letters  on  colors,  326 

Light  coach  oil,  238 

Linseed  oil  drier,  234 

Liquid  soap,  309 

Liquids,  weight  of,  375 

Litharge,  32 

Lithographic  varnish,  259 

Lithopone,  199 

Lixiviation,  3 

Logwood,  114 

Long  daub,  335 

Machine,  centrifugal,  13 
Machines,  grinding,  2 
Magnesium  sulphate,  33 


INDEX 


209 


Magnesite,  33 
Manganese  borate,  229 

linoleate,  231 

resinate,  233 
Mastic  varnish,  249 
Mat  finish,  340,  343,  316  (b} 
Mechanical  pulp,  357 
Medium  coach  oil,  239 
Mensuration  of  volume,  365 
Mercerization,  148 
Mercerized  cotton,  148 

dyeing  of,  149 
Metadinitrobenzene,  69 
Metallic  tannates,  163 
Methyl  benzoate,  66 
Methyl  violet  T  B,  98 
Methylene  Blue,  95 
Metric  weights,  equivalents  of, 

378 

Mill,  laboratory,  2 
Milling,  317  (ft) 
Monobrombenzene,  58 
Monochloracetic  acid,  54 
Mordant  color,  159,  160,  161,  162 

dyes,  109 
Multiples,  table  of,  379 

Naphthalene  |8,  81 

Naphthol  j8,  82 

Naphthol-3 : 6-disul phonic  acid  |8, 

84 

Naphthol-6-sulphonic  acid  |8,  83 
Naphthol  yellow  S,  92 
Naphthylamine  a,  86 
Nigrosine,  97 
Niobe  oil,  66 

Nitracetanilide  (para-),  78 
Nitraniline  (para-),  79 


Nitrobenzene,  68 
Nitronaphthalene  a,  85 
Nitrophenol  (ortho-  and  para-), 
70 

Oakes  bate,  314  (a) 
Oil,  light  coach,  238 

medium  coach,  239 

soluble  colors,  147 

stains,  284 

strong  coach,  240 

varnishes,  252 
One-bath  chrome,  317   (ft),  336, 

337,  338,  339 
Ooze  finish,  322 

black,  353 

brown,  352 

gray,  351 
Orange  II,  93 
Oropon,  314  (ft),  (c) 
Oven,  drying,  13 
Oxidation  colors,  187 

Paint,  apple  green,  277 
azure  blue,  271 
Brunswick  green,  280 
cement,  274 
cream,  265 
dark  blue,  270 
dark  lead,  276 
dark  olive  green,  279 
drab,  272 
flesh,  268 
Indian  red,  282 
light  blue,  269 
light  colonial,  264 
machine  gray,  275 
outside  green,  281 


210 


INDEX 


Paint,  outside  white,  263 

sage  green,  278 

slate,  273 

straw,  267 

white,  262 

yellow,  266 

Palm  oil  soap,  298,  304 
Pans,  vacuum,  7 
Paper,  355 

bleaching  of,  359 

colored,  363 

making,  360 
Para  Cresol,  61 
Para  Red,  226 
Parallelopipedon,     volume     of, 

367 
Patent  leather,  334 

varnish  for,  335 
Phenol,  60 
Pickling,  315,  317 
Picric  acid,  71 
Pigments,  189 
Pigskin  tannage,  320 
Potash  alum,  24 
Potassium  permanganate,  34 
Pressure  of  fluids,  376,  377 
Primary  colors,  326 
Printing  cotton,  188 
Prussian  blue,  190 
Puerine,  314  (d) 
Puering,  314 
Pulleys,  speed  of,  387 
Putty,  283 
Pyknometer,  16,  21 
Pyrolusite,  34 

Quebracho-tanned   sheep     skins, 
322 


R  Salt,  84 

Ready-mixed  paint.  260 
Red  oxide,  191 
Reel,  112 
Roasting,  8 
Rohm's  bate,  314  (b) 
Roller  mill,  292 
Rosin  size,  362 

soap,  307 

Round  timber,  volume  of,  282 
Rule  for  mixing  colors,  328 
Russia  finish,  344 
Rust  remover,  242 

Salicylic  acid,  73 

Sand  soap,  310 

Satin  white,  198 

Scales,  hydrometer,  16 

Scarlet  lake,  213 

Schaeffer's  salt,  83 

Scheele  green,  194 

Secondary  colors,  326 

Sheep   skins,   quebracho-tanned, 

322 

Shellac  varnish,  246 
Short  daub,  334 
Side  leather,  318 
Silk,  126 

dyeing  of,  129,  130 
Skins,  depilating  of,  317 
.     fleshing  of ,  3 1 7 

soaking  of,  312,  317 
Soaking,  317  (b) 
Soap,  293 

boiled,  303 

chipper,  294 

cold-made,  294 

cutter,  294 


INDEX 


211 


Soap,  dog,  302 

frame,  294 

green  castile,  295,  299 

half-boiled,  297 

kettle,  303 

laundry,  296,  301 

liquid,  309 

mill,  294 

palm  oil,  298,  304 

plodder,  294 

powder,  311 

press,  294 

rosin,  307 

sand,  310 

slabber,  294 

soft,  308 

tar,  300 
Soda  ash,  36 
Sodium  benzene  sulphonate,  59 

bisulphite,  38 

dichromate,  27 

silicate,  35 

sulphite,  39 

thiosulphate,  40 
Soft  soap,  308 
Sole  leather,  acid  hemlock,  332 

union,  333 

Solids,  weight  of,  374 
Specific  gravity,  apparatus  for.  16 

bottle,  16,  21 

table,  369 

Speed  of  pulleys,  387 
Sphere,  volume  of,  372 
Spirit  colors,  in,  146 

varnishes,  245 
Splits,  finish  for,  349 
Stain,  ash,  286 

chestnut,  288 


Stain,  dark  oak,  287 

mahogany,  291 

maple,  289 

oak, 286 

pine,  289 

walnut,  290 
Stains,  removal  of,  171 
Staking,  317 
Strain,  units  for,  383 
Strong  coach  oil,  240 
Sublimation,  14 
Substantive  dyes,  108 
Succinic  acid,  57 
Sulphanilic  acid  (para-),  76 
Sulphur  black  T,  101 

dyes,  172 

monochloride,  41 
Surface,  measure  of,  381 
Sweet-meat,  334 

Table  of  multiples,  319 
Tanning,  316 
Tanolin,  317 
Tar  soap,  300 

Thermometer  conversions,  364 
Timber  measure,  380 
Tool  varnish,  257 
Trichlormethane,  49 
Turkey  Red  on  cotton,  178 
TwaddelPs  hydrometer,  19 
Two-bath  chrome,  316 

Unhairing,  317 
Union  sole  leather,  333 

Vacuum  dryer,  13 
Varnish,  coach,  255 

collodion,  251 

dammar,  250 


212 


INDEX 


Varnish,  for  iron,  243 

mastic,  249 

remover,  241 

shellac,  246 
Vat  colors,  173 
Vermilion,  192,  193 
v;.olet,  lake,  209 
Volt,  390 
Volume,  mensuration  of;  365 

Washing,  5 
Water  glass,  35 


Waterproof  varnish,  258 

Watt,  394 

Weight  of  liquids,  375 

of  solids,  374 
Westphal  balance,  22 
Wolframite,  43 
Wood,  pulp,  356 
Wool,  114 

dyeing  of,  124 

Zinc  lime  vat,  174 
sulphate,  44 


MEMORANDA 


MEMORANDA 


MEMORANDA 


MEMORANDA 


MEMORANDA 


MEMORANDA 


MEMORANDA 


MEMORANDA 


MEMORANDA 


MEMORANDA 


MEMORANDA 


MEMORANDA 


A  SELECTED  LIST  OF  BOOKS  ON 

CHEMISTRY      AND       CHEMICAL 
TECHNOLOGY 

Published  by 

D.    VAN     NOSTRAND    COMPANY 
26    Park    Place  New    York 


American  Institute  of  Chemical  Engineers.  Transactions. 
8vo.  cloth.  Issued  annually.  Vol.  I.,  1908,  to  Vol. 
VIII. ,  1915,  now  ready.  each,  net,  $6.00 

Annual  Reports  en  the  Progress  of  Chemistry.  Issued 
annually  by  the  Chemical  Society.  8vo.  cloth.  Vol.  L, 
1904,  to  Vol.  XII.,  1915,  now  ready.  each,  net,  $2.00 

ASCH,  W.,  and  ASCH,  D.  The  Silicates  in  Chemistry  and 
Commerce.  Including  the  exposition  of  a  hexite  and 
pentite  theory  and  of  a  stereo-chemical  theory  of  gen- 
eral application.  Translated,  with  critical  notes  and 
additions,  by  Alfred  B.  Searle.  Illus.  6%  x  10.  cloth. 
476  pp.  net,  $6.00 

ASHLEY,  R.  H.  Chemical  Calculations.  Illustrated. 
5}4x7^.  cloth.  286pp.  net,  $2.00 

BAILEY,  R.  0.  The  Brewer's  Analyst.  Illustrated.  8vo. 
cloth.  423  pp.  net,  $5.00 

BARKER,  A.  F.,  and  MIDGLEY,  E.  Analysis  of  Woven 
Fabrics.  85  illustrations.  5^x8^.  cloth.  319  pp. 

net,  $3.00 

BEADLE,  C.  Chapters  on  Papermaking.  Illustrated. 
i2mo.  cloth.  5  volumes.  each,  net,  $2.00 

BEAUMONT,  R.  Color  in  Woven  Design.  A  treatise  on 
the  science  and  technology  of  textile  coloring  (woolen, 


2  D.    VAN   NOSTRAND    COMPANY'S 

[worsted,  cotton  and  silk  materials).  New  Edition,  re- 
written and  enlarged.  39  colored  plates.  367  illustra- 
tions. 8vo.  cloth.  369  pp.  net,  $6.00 

BECHHOLD,  H.  Colloids  in  Biology  and  Medicine. 
Translated  by  J.  G.  Bullowa,  M.D.  In  Press. 

BENNETT,  HUGH  G.  The  Manufacture  of  Leather, 
no  illustrations.  8vo.  cloth.  438  pp.  net,  $4.50 

BERNTHSEN,  A.  A  Text-book  of  Organic  Chemistry. 
English  translation.  Edited  and  revised  by  J.  J.  Sud- 
borough.  Illus.  I2mo.  cloth.  690  pp.  net,  $2.50 

BERSCH,  J.  Manufacture  of  Mineral  Lake  Pigments. 
Translated  by  A.  C.  Wright.  43  illustrations.  8vo. 
cloth.  476  pp.  net,  $5.00 

BEVERIDGE,  JAMES.  Papennaker's  Pocketbook.  Spe- 
cially compiled  for  paper  mill  operatives,  engineers, 
chemists  and  office  officials.  Second  and  Enlarged 
Edition.  Illus.  I2mo.  cloth.  211  pp.  net,  $4.00 

BIRCHMORE,  W.  H.  The  Interpretation  of  Gas  Analyses. 
Illustrated.  I2mo.  cloth.  75  pp.  net,  $1.25 

BLASDALE,  W.  C.  Principles  of  Quantitative  Analysis. 
An  introductory  Course.  Second  Edition,  revised  and 
enlarged.  70  illus.  5*4  X7/^-  cloth.  414  pp. 

net,  $2.50 

BLtiCHER,   H.     Modern   Industrial   Chemistry.     Trans 
lated  by  J.   P.   Millington.     Illus.     8vo.     cloth.     795 
pp.  net,  $7.50 

BLYTH,  A.  W.  Foods:  Their  Composition  and  Analysis. 
A  manual  for  the  use  of  analytical  chemists,  with  an 
introductory  essay  on  the  History  of  Adulterations. 
Sixth  Edition,  thoroughly  revised,  enlarged  and  re- 
written. Illustrated.  8vo.  cloth.  634  pp.  $7.50 

Poisons :  Their  Effects  and  Detection.     A  manual  for 

the  use  of  analytical  chemists  and  experts,  with  an 


LIST    OF    CHEMICAL   BOOKS 


introductory  essay  on  the  Growth  of  Modern  Toxicol- 
ogy. Fourth  Edition,  revised,  enlarged  and  rewritten. 
Illustrated.  8vo.  cloth.  772  pp.  $7.50 

BOCKMANN,  F.  Celluloid ;  Its  Eaw  Material,  Manufac- 
ture, Properties  and  Uses.  49  illustrations.  I2mo.  cloth. 
1 20  pp.  net,  $2.50 

BOOTH,  WILLIAM  H.  Water  Softening  and  Treatment. 
91  illustrations.  8vo.  cloth.  310  pp.  net,  $2.50 

BOURCART,  E.  Insecticides,  Fungicides,  and  Weed 
Killer?.  Translated  by  D.  Grant.  8vo.  cloth.  500  pp. 

net,  $4.50 

BOURRY,  EMILE.  A  Treatise  on  Ceramic  Industries. 
A  complete  manual  for  pottery,  tile,  and  brick  manu- 
facturers. A  revised  translation  from  the  French  by 
Alfred  B.  Searle.  308  illustrations.  12  mo.  cloth. 
488  pp.  net,  $5.00 

BBISLEE,  F.  J.  An  Introduction  to  the  Study  of  Fuel. 
A  text-book  for  those  entering  the  engineering,  chem- 
ical and  technical  industries.  60  ill.  8vo.  cloth.  293 
pp.  (Outlines  of  Industrial  Chemistry.)  net,  $3.00 

BROWN,  HAROLD.  Rubber,  Its  Sources,  Cultivation  and 
Preparation.  111.  6  x  8^4.  237  pp.  $2.00 

BRUCE,  EDWIN  M.  Detection  of  the  Common  Food 
Adulterants.  Illus.  i2mo.  cloth.  90  pp.  net,  $1.25 

BUSKETT,  E.  W.  Fire  Assaying.  A  practical  treatise  on 
the  fire  assaying  of  gold,  silver  and  lead,  including 
descriptions  of  the  appliances  used.  Illustrated.  I2mo. 
cloth.  112  pp.  net,  $1.25 

BYERS,  HORACE  G.,  and  KNIGHT,  HENRY  G.  Notes 
on  Qualitative  Analysis.  Second  Edition,  revised. 
8vo.  cloth.  192  pp.  net,  $1.50 

CAVEN,  R.  M.,  and  LANDER,  G.  D.  Systematic  Inor- 
ganic Chemistry  from  the  Standpoint  of  the  Periodic 


D.    VAN    NO  STRAND    COMPANY'S 


Law.  A  text-book  for  advanced  students.  Illustrated. 
i2mo.  cloth.  390  pp.  net,  $2.00 

CHRISTIE,  W.  W.  Boiler-waters,  Scale,  Corrosion,  Foam- 
ing. 77  illustrations.  8vo.  cloth.  242  pp.  net,  $3.00 
-Water,  Its  Purification  and  Use  in  the  Industries. 
79  illus.,  3  folding  plates,  2  colored  inserts.  I2mo. 
cloth.  230  pp.  net,  $2.00 

CHURCH'S  Laboratory  Guide.  A  manual  of  practical 
chemistry  for  colleges  and  schools,  specially  arranged 
for  agricultural  students.  Ninth  Edition,  revised  and 
partly  rewritten  by  Edward  Kinch.  Illustrated.  8vo. 
cloth,  365  pp.  net,  $2.50 

CORNWALL,  H.  B.  Manual  of  Blow-pipe  Analysis. 
Qualitative  and  quantitative.  With  a  complete  system 
of  determinative  mineralogy.  Sixth  Edition,  revised. 
70  illustrations.  8vo.  cloth.  310  pp.  net,  $2.50 

CROSS,  C.  F.,  BEVAN,  E.  J.,  and  SINDALL,  R.  W. 
Wood  Pulp  and  Its  Uses.  With  the  collaboration  of 
W.  N.  Bacon.  30  illustrations.  I2mo.  cloth.  281 
pp.  (Van  Nostrand's  Westminster  Series.)  net,  $2.00 

d'ALBE,  E.  E.  F.  Contemporary  Chemistry.  A  survey 
of  the  present  state,  methods,  and  tendencies  of  chemi- 
cal science.  I2mo.  cloth.  172  pp.  net,  $1,25 

DANBY,  ARTHUR.  Natural  Rock  Asphalts  and  Bitu- 
mens. Their  Geology,  History,  Properties  and  Indus- 
trial Application.  Illustrated.  I2mo.  cloth.  254  pp. 

net,  $2.50 

DEERR,  N.  Cane  Sugar.  280  illustrations.  6^2x9^. 
cloth.  608  pp.  net,  $7.00 

DUMESNY,  P.,  and  NOYER,  J.  Wood  Products,  Dis- 
tillates and  Extracts.  Translated  by  D.  Grant.  103 
illustrations.  8vo.  cloth.  320  pp.  net,  $4.50 

DUNSTAN,  A.  E.,  and  THOLE,  F.  B.  A  Text-book  of 
Practical  Chemistry  for  Technical  Institutes.  52  illus- 
trations. I2mo.  cloth.  345  pp.  net,  $1.40 


LIST    OF    CHEMICAL    BOOKS 


DYSON,  S.  S.,  and  CLARKSON,  S.  S.  Chemical  Works, 
Their  Design,  Erection,  and  Equipment.  80  illustra- 
tions, 9  folding  plates.  8vo.  cloth.  220  pp.  net,  $7.50 

ELIOT,  C.  W.,  and  STOKER,  F.  H.  A  Compendious  Man- 
ual of  Qualitative  Chemical  Analysis.  Revised  with 
the  co-operation  of  the  authors,  by  William  R. 
Nichols.  Twenty-second  Edition,  newly  revised  by 
W.  B.  Lindsay.  111.  I2mo.  cloth.  205  pp.  net,  $1.25 

ELLIS,  C.  Hydrogenation  of  Oils,  Catalysis  and  Catalyzers, 
and  the  Generation  of  Hydrogen.  Second  Edition,  re- 
vised and  enlarged.  In  Press 

ENNIS,  WILLIAM  D.  Linseed  Oil  and  Other  Seed  Oils. 
"An  industrial  manual.  88  illustrations.  8vo.  cloth. 
336  pp.  net,  $4.00 

ERMEN,  W.  F.  A.  The  Materials  Used  in  Sizing.  Their 
chemical  and  physical  properties,  and  simple  methods 
for  their  technical  analysis  and  valuation.  Illustrated. 
i2mo.  cloth.  130  pp.  net,  $2.00 

FAY,  IRVING  W.  The  Chemistry  of  the  Coal-tar  Dyes. 
8vo.  cloth.  473  pp.  net,  $4.00 

FERNBACH,  R.  L.  Chemical  Aspects  of  Silk  Manu- 
facture. i2mo.  cloth.  84  pp.  net,  $1.00 

Glue  and  Gelatine.  A  practical  treatise  on  the 

methods  of  testing  and  use.  Illustrated.  8vo.  cloth. 
208  pp.  net,  $3.00 

FIRTH,  J.  B.  Practical  Physical  Chemistry.  111.  5x7. 
cloth.  189  pp.  net,  $1.00 

FISCHER,  E.  Introduction  to  the  Preparation  of  Or- 
ganic Compounds.  Translated  from  the  new  (eighth) 
German  edition  by  R.  V.  Stanford.  Illustrated. 
i2mo.  cloth.  194  pp.  net,  $1.25 

FOYE,  J.  C.  Chemical  Problems.  Fourth  Edition,  revised 
and  enlarged.  i6mo.  cloth.  145  pp.  (Van  Nos- 
trancl  Science  Series,  No.  69.)  $0.50 

FRANZEN,  H.     Exercises  in  Gas  Analysis.     Translated 


6  D.   VAN  NO  STRAND  COMPANY'S 

from  the  first  German  edition,  with  corrections  and 
additions  by  the  author,  by  Thomas  Callan.  30  dia- 
grams. 5x7^4.  cloth.  127  pp.  net,  $1.00 

FRITSCH,  J.  The  Manufacture  of  Chemical  Manures. 
Translated  from  the  French,  with  numerous  notes,  by 
Donald  Grant.  69  illus.,  108  tables.  Svo.  cloth. 
355  PP-  net,  $4.00 

GROSSMANN,  J.  Ammonia  and  Its  Compounds.  Illus- 
trated. I2mo.  cloth.  151  pp.  net,  $1.25 

HALE,  WILLIAM  J.  Calculations  in  General  Chemistry. 
With  definitions,  explanations  and  problems.  Fifth 
Edition,  revised.  I2mo.  cloth.  185  pp.  net,  $1.00 

HALL,  CLARE  H.  Chemistry  of  Paints  and  Paint  Ve- 
hicles. Svo.  cloth.  141  pp.  net,  $2.00 

HILDITCH,  T.  P.  A  Concise  History  of  Chemistry. 
16  diagrams.  I2mo.  cloth.  273  pp.  net,  $1.25 

HILL.  C.  W.  Laboratory  Manual  and  Notes  in  Beginning' 
Chemistry.  Second  Revised  Edition.  In  Press 

HOYT,  W.  F.  Chemistry  by  Experimentation,  Including 
Qualitative  Analysis.  A  laboratory  manual  for  the 
first  year,  course.  In  Press 

HiiBNER,  JULIUS.  Bleaching  and  Dyeing  of  Vegetable 
Fibrous  Materials.  95  illus.  (many  in  two  colors). 
Svo.  cloth.  457  pp.  net,  $5.00 

HUDSON,  0.  F.  Iron  and  Steel.  An  introductory  text- 
book for  engineers  and  metallurgists.  With  a  section 
on  Corrosion  by  Guy  D.  Bengough.  47  illus.  Svo. 
cloth.  184  pp.  net,  $2.00 

HURST,  GEO.  H.  Lubricating  Oils,  Fats  and  Greases. 
Their  origin,  preparation,  properties,  uses,  and  analy- 
sis. Third  Edition,  revised  and  enlarged,  by  Henry 
Leask.  74  illus.  Svo.  cloth.  405  p.  net,  $4.00 

HURST,  G.  H.,  and  SIMMONS,  W.  H.    Textile  Soaps  and 


LIST    OF    CHEMICAL    BOOKS 


Oils.      Second  Edition,  revised  and  partly  rewritten. 
ii  illustrations.    5^x8^.    204  pp.  net,  $3.00 

HYDE,  FREDERIC  S.  Solvents,  Oils,  Gums,  Waxes  and 
Allied  Substances.  5>4X8/^-  cloth.  182  pp. 

net,  $2.00 

INGLE,  HERBERT.  Manual  of  Agricultural  Chemistry. 
Illustrated.  8vo.  cloth.  388  pp.  net,  $3.00 

JOHNSTON,  J.  F.  W.  Elements  of  Agricultural  Chem- 
istry. Revised  and  icwritten  by  Charles  A.  Gameron 
and  C.  M.  Aikman.  Nineteenth  Edition.  Illustrated. 
I2mo.  cloth.  502  pp.  $2.60 

JONES,  HARRY  C.  A  New  Era  in  Chemistry.  Some  of 
the  more  important  developments  in  general  chemis- 
try during  the  last  quarter  of  a  century.  Illustrated. 
i2mo.  cloth.  336  pp.  net,  $2.00 

-The   Theory  of   Solution.     Edited  by  E.   E.   Reid. 
Illustrated.    6x9.    cloth.    370  pp.  In  Press 

XEMBLE,  W.  F.,  and  UNDERBILL,  C.  R.  The  Periodic 
Law  and  the  Hydrogen  Spectrum.  Illustrated.  8vo. 
paper.  16  pp.  net,  $0.50 

KERSHAW,  J.  B.  C.  Fuel,  Water,  and  Gas  Analysis,  for 
Steam  Users.  50  ill.  8vo.  cloth.  178  pp.  net,  $2.50 

—  Electro-Thermal  Methods  of  Iron  and  Steel  Produc- 
tion.    With  an  introduction   by   Dr.   J.   A.   Fleming, 
F.R.S.     50  tables,  92  illustrations.     5>^x8>4.     cloth. 
262  pp.  net,  $3.00 

XNOX,  JOSEPH.  Physico-chemical  Calculations.  i2mo. 
cloth.  196  pp.  net,  $1.00 

—  The  Fixation  of  Atmospheric  Nitrogen.     Illustrated. 
5x7^.     cloth.     1 20  pp.     (Van  Nostrand's  Chemical 
Monographs.)  net,  $0.75 

KOLLER,  T.  Cosmetics.  A  handbook  of  the  manufac- 
ture, employment  and  testing  of  all  cosmetic  materials 
and  cosmetic  specialties.  Translated  from  the  German 
by  Charles  Salter.  8vo.  cloth.  262  pp.  net,  $2.50 


*  D.    VAN   NO  STRAND    COMPANY'S 

-Utilization  of  Waste  Products.  A  treatise  on  the 
rational  utilization,  recovery  and  treatment  of  waste 
products  of  all  kinds.  Second  Revised  and  Enlarged 
Edition.  22  illustrations.  sH  x  ^A-  cloth.  336  pp. 

net,  $3.00 

KOPPE,  S.  W.  Glycerine.  Its  introduction,  uses  and 
examination.  For  chemists,  perfumers,  soapmakers, 
pharmacists,  and  explosives  technologists.  7  illustra- 
tions. 5^x7^.  260  pp.  $2.50 

KREMANN,  R.  The  Application  of  Physico-chemical 
Theory  to  Technical  Processes  and  Manufacturing' 
Methods.  Authorized  translation  by  Harold  E.  Potts, 
M.Sc.  35  diagrams.  8vo.  cloth.  215  pp.  net,  $2.50 

KRETSCHMAR,  KARL.  Yarn  and  Warp  Sizing  in  All 
Its  Branches.  Translated  from  the  German  by  C. 
Salter.  122  illus.  Svo.  cloth.  192  pp.  net,  $4.00 

LAMBORN,  L.  I.    Modern  Soaps,  Candles  and  Glycerin. 

224  illustrations.     Svo.     cloth.     700  pp.         net,  $7.50 

—  Cotton  Seed  Products.    79  illus.  Svo.  cloth.  253  pp. 

net,  $3.00 

LASSAR-COHN.  Introduction  to  Modern  Scientific 
Chemistry.  In  the.  form  of  popular  lectures  suited  for 
University  Extension  students  and  general  readers. 
Translated  from  the  Second  German  Edition  by  M.  M. 
Pattison  Muir.  Illus.  I2mo.  cloth.  356  pp.  $2.00 

LETTS,  E.  A.  Some  Fundamental  Problems  in  Chemis- 
try :  Old  and  New.  44  illustrations.  Svo.  cloth.  236 
pp.  net,  $2.00 

LLOYD,  STRAUSS  L.    Fertilizer  Materials.  In  Press 

LUNGE,  GEORGE.  Technical  Methods  of  Chemical 
Analysis.  Translated  from  the  Second  German  Edition 
by  Charles  A.  Keane,  with  the  collaboration  of  eminent 
experts.  Complete  in  three  volumes.  Six  parts.  448 
illustrations.  6^x9^.  cloth.  3494  PP-  net,  $48.00 


[AST    OF    CHEMICAL    BOOKS 


Vol.  I.   (in  two  parts).     201  illustrations.  6T/ 

cloth.     1024  pp.  net,  $15.00 

Vol.  II.  (in  two  parts).     149  illustrations.  6l/2  *9l/2- 

cloth.     1294  pp.  net,  $18.00 

Vol.  III.  (in 'two  parts).     98  illustrations.  6l/2  XQ^. 

cloth.    1174  pp.  net,  $18.00 

—  Technical  Chemists'  Handbook.     Tables  and  meth- 


ods of  analysis  for  manufacturers  of  inorganic  chemi- 
cal products.  Second  Edition,  revised.  Illus.  I2mo. 
leather.  276  pp.  net,  $3.50 

Coal,  Tar   and  Ammonia.    Fifth  and  Enlarged  Edi- 


tion. In  three  volumes,  not  sold  separately.  111.  6x9. 
cloth.  1600  pp.  net,  $1,8.00 

The   Manufacture   of   Sulphuric   Acid   and   Alkali. 

A  theoretical  and  practical  treatise. 
Vol.   I.     Sulpliuric  Acid.     Fourth  Edition,  enlarged. 
In  three  parts,  not  sold  separately.     543  illustrations. 
8vo.     cloth.     1665  pp.  net,  $18.00 

Vol.  II.  Sulphate  of  Soda,  Hydrochloric  Acid,  Leblanc 
Soda.  Third  Edition,  much  enlarged.  In  two  parts, 
not  sold  separately.  335  illustrations.  8vo.  cloth. 
1044  pp.  net,  $15.00 

Vol.  III.  Ammonia  Soda.  Various  Processes  of  Al- 
kali-making, and  the  Chlorine  Industry.  181  illus- 
trations. 8vo.  cloth.  784  pp.  net,  $10.00 
Vol.  IV.  Electrolytical  Methods.  In  Press. 

Technical  Gas  Analysis.     143  illustrations.     6x9. 

cloth.    422  pp.  net,  $4.00 

McINTOSH,  JOHN  G.  The  Technology  of  Sugar.  Third 
Edition,  revised  and  enlarged.  244  illustrations. 
6x8j4.  540pp.  $5.00 

McINTOSH,  JOHN  G.  The  Manufacture  of  Varnish  and 
Kindred  Industries.  Illus.  8vo.  cloth.  In  3  volumes. 


io          D.  VAN  NOSTRAND  COMPANY'S 

Vol.  I.  Oil  Crushing,  Refining  and  Boiling;  Manu- 
facture of  Linoleum ;  Printing  and  Lithographic  Inks ; 
India  Rubber  Substitutes.  29  illus.  160  pp.  net,  $3.50 
Vol.  II.  Varnish  Materials  and  Oil  Varnish  Making. 
66  illus.  216  pp.  net,  $4.00 

Vol.  III.  Spirit  Varnishes  and  Varnish  Materials. 
64  illus.  492  pp.  net,  $4.50 

MARTIN,  G.  Triumphs  and  Wonders  of  Modern  Chem- 
istry. A  popular  treatise  on  modern  chemistry  and 
its  marvels  written  in  non-technical  language.  76  il- 
lustrations. i2tno.  cloth.  358  pp.  net,  $2.00 
-Modern  Chemistry  and  Its  Wonders.  A  popular 
account  of  some  of  the  more  remarkable  recent  ad- 
vances in  chemical  science.  65  illustrations.  $%  x  724- 
267  pp.  $2.00 

MELICK,  CHARLES  W.  Dairy  Laboratory  Guide.  52 
illustrations.  I2mo.  cloth.  135  pp.  net,  $1.211 

MERCK,  E.  Chemical  Reagents :  Their  Purity  and  Tests. 
Second  Edition,  revised.  6x9.  cloth.  210  pp.  $1.00 

MIERZINSKI,  S.  The  Waterproofing  of  Fabrics.  Trans- 
lated from  the  German  by  A.  Morris  and  H.  Robson. 
Second  Edition,  revised  and  enlarged.  29  illustrations. 
5x7^.  140  pp.  net,  $2.50 

MITCHELL,  C.  A.  Mineral  and  Aerated  Waters,  in 
illustrations.  8vo.  cloth.  244  pp.  net,  $3.00 

MITCHELL,  C.  A.,  and  PRIDEAITX,  R.  M.  Fibres  Used 
in  Textile  and  Allied  Industries.  66  illustrations. 
8vo.  cloth.  208  pp.  net,  $3.00 

MTTNBY,  A.  E.  Introduction  to  the  Chemistry  and 
Physics  of  Building  Materials.  Illus.  8vo.  cloth.  365 
pp.  (Van  Nbstrand's  Westminster  Series.)  net,  $2.00 

MURRAY,  J.  A.  Soils  and  Manures.  33  illustrations. 
8vo.  cloth.  367  pp.  (Van  Nostrand's  Westminster 
Series.)  net,  $2.00 


LIST    OF    CHEMICAL   BOOKS  n 

NEAVE,  G.  B.,  and  HEILBKON,  I.  M.  The  Identifica- 
tion of  Organic  Compounds.  i2mo.  cloth,  in  pp. 

net,  $1.25 
NORTH,    H.    B.      Laboratory    Experiments    in    General 

Chemistry.     Second  Edition,  revised.     36  illustrations. 
5)4x724.     cloth.     212  pp.  net,  $1.00 

OLSEN,  J.  C.  A  Textbook  of  Quantitative  Chemical 
Analysis  by  Gravimetric  and  Gasometric  Methods. 
Including  74  laboratory  exercises  giving  the  analysis 
of  pure  salts,  alloys,  minerals  and  technical  products. 
Fifth  Edition,  revised  and  enlarged.  Illustrated. 
6l/2  x  9^4.  cloth.  576  pp.  net,  $3.50 

PARRY,  ERNEST  J.  The  Chemistry  of  Essential  Oils 
and  Artificial  Perfumes.  Second  Edition,  thoroughly 
revised  and  greatly  enlarged.  Illustrated.  8vo.  cloth. 
554  PP-  ne*>  $5.00. 

Food  and  Drugs.     In  2  volumes.    Illus.    8vo.  cloth. 

Vol.  I.     The  Analysis  of  Food  and  Drugs  (Chemical 
and  Microscopical).    59  illus.    724  pp.  net,  $7.50 

Vol.   II.     The  Sale  of  Food  and  Drugs  Acts,  1873- 
1907.     184  pp.  net,  $3.00 

PARTINGTON,  JAMES  R.  A  Text-book  of  Thermo- 
dynamics (with  special  reference  to  Chemistry).  91 
diagrams.  8vo.  cloth.  550  pp.  net,  $4.00 

-Higher    Mathematics    for    Chemical    Students.      44 
diagrams.     i2mo.     cloth.     272  pp.  net,  $2.00 

PERKIN,  F.  M.,  and  JAGGERS,  E.  M.  Textbook  of  Ele- 
mentary Chemistry.  77  illustrations.  4^4  x  7.  cloth. 
342  pp.  net,  $1.00 

PLATTNER'S  Manual  of  Qualitative  and  Quantitative 
Analysis  with  the  Blowpipe.  Eighth  Edition,  revised. 
Translated  by  Henry  B.  Cornwall,  assisted  by  John 
H.  Caswell,  from  the  Sixth  German  Edition,  by  Fried- 
rich  Kolbeck.  87  ill.  8vo.  cloth.  463  pp.  net,  $4.00 


12         D.    VAN    NO  STRAND    COMPANY'S 

POLLEYN,  F.  Dressings  and  Finishings  for  Textile 
Fabrics  and  Their  Application.  Translated  from  the 
Third  German  Edition  by  Chas.  Salter.  60  illustra- 
tions. 8vo.  cloth.  279  pp.  net,  $3.00 

POPE,  F.  G.  Modern  Research  in  Organic  Chemistry. 
261  diagrams.  I2mo.  cloth.  336  pp.  net,  $2.25 

PORRITT,  B.  D.  The  Chemistry  of  Rubber.  5x7^. 
cloth.  100  pp.  [Van  Nostrand's  Chemical  Mono- 
graphs.) net,  $0.75 

POTTS,  HAROLD  E.  Chemistry  of  the  Rubber  Industry. 
8vo.  cloth.  163  pp.  net,  $2.00 

PRESCOTT,  A.  B.  Organic  Analysis.  A  manual  of  the 
descriptive  and  analytical  chemistry  of  certain  carbon 
compounds  in  common  use.  Sixth  Edition.  Illus- 
trated. 8vo.  cloth.  533  pp.  $5.00 

PRESCOTT,  A.  B.,  and  JOHNSON,  0.  C.  Qualitative 
Chemical  Analysis.  Seventh  Edition,  revised  and  en- 
larged by  John  C.  Olsen,  A.M.,  Ph.D.  6^x9^. 
cloth.  440  pp.  net,  $3.50 

PRESCOTT,  A.  B,  and  SULLIVAN,  E.  C.  First  Book  in 
Qualitative  Chemistry.  For  studies  of  water  solution 
and  mass  action.  Eleventh  Edition,  entirely  rewritten. 
i2mo.  cloth.  150  pp.  net,  $1.50 

PRIDEATJX,  E.  B.  R.  Problems  in  Physical  Chemistry 
with  Practical  Applications.  13  diagrams.  8vo.  cloth. 
323  pp.  net,  $2.00 

RICHARDS,  W.  A.,  and  NORTH,  H.  B.     A  Manual  of 
Cement  Testing.     For  the  use  of  engineers  and  chem- 
ists  in   colleges   and   in   the   field.      56   illustrations. 
I2mo.     cloth.     147  pp.  net,  $1.50 

RIDEAL,  S.  Glue  and  Glue  Testing.  Second  Edition, 
revised  and  enlarged.  14  illustrations.  5^x8^. 
cloth.  194  pp.  net,  $4.00 


LIST    OF    CHEMICAL   BOOKS  13 

ROGERS,  ALLEN  (Editor).  Industrial  Chemistry.  A 
manual  for  the  student  and  manufacturer.  Second 
Edition,  thoroughly  revised  and  enlarged.  Written 
by  a  staff  of  eminent  specialists.  304  illustrations. 
61/2x9%.  cloth.  1026  pp.  net,  $5.00 

ROGERS,  ALLEN.  Elements  of  Industrial  Chemistry. 
An  abridgement  of  The  Manual  of  Industrial  Chem- 
istry. 117  illustrations,  I  folding  plate.  5^2x8. 
521  pp.  net,  $3.00 

—  A  Laboratory  Guide  of  Industrial  Chemistry.    Illus- 
trated.   8vo.    cloth.     170  pp.  net,  $1.50 

ROHLAND,  PAUL.  The  Colloidal  and  Crystalloidal  State 
of  Matter.  Translated  by  W.  J.  Britland  and  H.  E. 
Potts.  i2mo.  cloth.  54  pp.  ,  net,  $1.25 

ROTH,  W.  A.  Exercises  in  Physical  Chemistry.  Author- 
ized translation  by  A.  T.  Cameron.  49  illustrations. 
8vo.  cloth.  208  pp.  net,  $2.00 

SCHERER,  R.  Casein:  Its  Preparation  and  Technical 
Utilization.  Translated  from  the  German  by  Charles 
Salter.  Second  Edition,  revised  and  enlarged.  Il- 
lustrated. 8vo.  cloth.  196  pp.  net,  $3.00 

SCHIDROWITZ,  P.  Rubber.  Its  Production  and  Indus- 
trial Uses.  Plates,  83  illus.  8vo.  cloth.  320  pp. 

net,$5.00 

SCHWEIZER,  V.  Distillation  of  Resins,  Resinate  Lakes 
and  Pigments.  Illustrated.  8vo.  cloth,  i83pp.net,  $3.50 

SCOTT,  W.  W.  Qualitative  Chemical  Analysis.  A  labo- 
ratory manual.  Second  Edition,  thoroughly  revised. 
Illus.  8vo.  cloth.  1 80  pp.  net,  $1.50 

SCOTT,  W.  W.  (Editor).  Technical  Methods  of  Analysis. 
111.  6x9.  600  pp.  In  Press 

SCUDDER,  HEYWARD.  Electrical  Conductivity  .and 
lonization  Constants  of  Organic  Compounds.  6x9. 
cloth.  575  pp.  net,  $3.00 


14         D.    VAN   NOSTRAND    COMPANY'S 

SEARLE,  ALFRED  B.  Modern  Brickmaking.  260  illus- 
trations. 8vo.  cloth.  449  pp.  net,  $5.00 
-Cement,  Concrete  and  Bricks.  113  illustrations. 
5l/2X%lA.  cloth.  415  pp.  net,  $3.00 

SEIDELL,  A.  Solubilities  of  Inorganic  and  Organic  Sub- 
stances. A  handbook  of  the  most  reliable  quantitative 
solubility  determinations.  Second  Printing,  corrected. 
8vo.  cloth.  367  pp.  net,  $3.00 

SENTER,  G.  Outlines  of  Physical  Chemistry.  Second 
Edition,  revised.  Illus.  I2mo.  cloth.  401  pp.  $1.75 

A  Text-book  of  Inorganic  Chemistry.  90  illustra- 
tions. i2mo.  cloth.  595  pp.  net,  $1.75 

SEXTON,  A.  H.  Fuel  and  Refractory  Materials.  Second 
Ed.,  revised.  104  illus.  I2mo.  cloth.  374  pp.  net,  $2.00 

Chemistry  of  the  Materials  of  Engineering.  Illus. 

I2mo.  cloth.  344  pp.  net,  $2.50 

SIMMONS,  W.  H.,  and  MITCHELL,  C:  A.  Edible  Fats 
and  Oils.  Their  composition,  manufacture  and  analy- 
sis. Illustrated.  8vo.  cloth.  164  pp.  net,  $3.00 

SINDALL,  R.  W.  The  Manufacture  of  Paper.  58  illus. 
8vo.  cloth.  285  pp  .  (Van  Nostrand's  Westminster 
Series.)  net,  $2.00 

SINDALL,  R.  W.,  and  BACON,  W.  N.  The  Testing  of 
Wood  Pulp.  A  practical  handbook  for  the  pulp  and 
paper  trades.  Illus.  8vo.  cloth.  150  pp.  net,  $2.50 

SMITH,  J.  C.  The  Manufacture  of  Paint.  A  manual  for 
paint  manufacturers,  merchants  and  painters.  Second 
Edition,  revised  and  enlarged.  80  illustrations.  5^  x 
8^.  cloth.  286  pp.  net,  $3.50 

SMITH,  W.  The  Chemistry  of  Hat  Manufacturing. 
Revised  and  edited  by  Albert  Shonk.  Illustrated. 
I2mo.  cloth.  132  pp.  ,  net,  $3.00 

SOTITHCOMBE,  J.  E.  Chemistry  of  the  Oil  Industries. 
Illus.  8vo.  cloth.  209  pp.  net,  $3.00 


LIST    OF    CHEMICAL    BOOKS  15 

SPEYERS,  C.  L.    Text-book  of  Physical  Chemistry.      20 

illustrations.    8vo.    cloth.    230  pp.  net,  $2.25 

SPIEGEL,   L.     Chemical  Constitution  and  Physiological 

Action.       Translated    by    C.    Luedeking    and    A.    C. 

Boylston.     5x7^2.     cloth.     ;6o  pp.  net,  $1.25 

STEVENS,  H.  P.     Paper  Mill  Chemist.      67  illustrations. 

82  tables.     i6mo.    cloth.    280  pp.  net,  $2.50 

SUDBOROUGH,  J.  J.,  and  JAMES,  J.  C.     Practical  Or- 
ganic Chemistry.       92    illustrations.       I2mo.       cloth. 

394  PP-  net,  $2.00 

TERR¥,    H.   L.      India   Rubber   and   Its    Manufacture. 

1 8  illustrations.     8vo.     cloth.     303  pp.      (Van   Nos- 

trand's  Westminster  Series.)  net,  $2.00 

TITHERLEY,    A.    W.      Laboratory    Course    of    Organic 

Chemistry,    Including    Qualitative    Organic    Analysis. 

Illustrated.    8vo.    cloth.    235  pp.  net,  $2.00 

TOCH,  M.     Chemistry  and  Technology  of  Paints.  Second 

Edition,  revised  and  enlarged.     111.     6x9.     373  pp. 

net,  $4.00 
TOCH,  M.    Materials  for  Permanent  Painting.  A  manual 

for  manufacturers,  art  dealers,  artists,  and  collectors. 

With    full-page    plates.      Illustrated.      I2mo.      cloth. 

208  pp.  net,  $2.00 

TUCKER,  J.  H.     A  Manual  of  Sugar  Analysis.     Sixth 

Edition.    43  illustrations.    Svo.    cloth.    353  pp.    $3.50 
UNDERWOOD,  N.,  and  SULLIVAN,  T.  V.    Chemistry  and 

Technology  of  Printing  Inks.    9    illustrations.      6x9. 

cloth.     145  pp.  net,  $3.00 

VAN  NOSTRAND'S  Chemical  Annual.     Edited  by  John 

C.  Olsen  and  Alfred  Melhado.    A  handbook  of  useful 

data   for  analytical   manufacturing  and   investigating 

chemists  and  chemical  students.   Third  Issue,  enlarged. 

5x7^.    leather.    683  pp.  net,  $2.50 

VINCENT,    C.      Ammonia    and   Its    Compounds.     Their 


j6  D.  VAN  NOSTRAND  COMPANY'S 


manufacture  and  uses.     Translated  from  the  French 
by  M.  J.  Salter.   32  ill.  8vo.   cloth.    113  pp.     net,  $2.00 

VON  GEORGIEVICS,  G.  Chemical  Technology  of  Textile 
Fibres.  Translated  from  the  German  by  Charles 
Salter.  47  illustrations.  8vo.  cloth.  320  pp.  net,  $4.50 

Chemistry  of  Dyestuffs.  Translated  from  the  Sec- 
ond German  Edition  by  Charles  Salter.  8vo.  cloth. 
412  pp.  net,  $4.50 

VOSMAER,  A.  Ozone,  Its  Manufacture,  Properties  and 
Uses.  75  illustrations.  6x9.  cloth.  210  pp.  net,  $2.50 

WADMORE,  J.  M.  Elementary  Chemical  Theory.  Illus. 
i2mo.  cloth.  286  pp.  net,  $1.50 

WALKER,  JAMES.  Organic  Chemistry  for  Students  of 
Medicine.  Illus.  6x9.  cloth.  328  pp.  net,  $2.50 

WALSH,  J.  J.  Mining  and  Mine  Ventilation.  26  illus 
8vo.  cloth.  192  pp.  net,  $2.00 

WARNES,  A.  R.  Coal  Tar  Distillation  and  Working  Up 
of  Tar  Products.  67  illustrations.  5^4  x  8^.  cloth. 
197  pp.  net,  $2.50 

WHITE,  C.  H.  Methods  in  Metallurgical  Analysis.  106 
illustrations.  5x7^.  cloth.  365pp.  net,  $2.50 

WHITE,  G.  F.  A  Laboratory  and  Class-room  Guide  to 
Qualitative  Chemical  Analysis.  5x7.  cloth.  178  pp. 

net,  $1.25 

WILSON,  F.  J.,  and  HEILBRON,  I.  M.  Chemical  Theory 
and  Calculations.  An  elementary  text-book.  Illus.,  3 
folding  plates.  I2mo.  cloth.  145  pp.  net,  $1.00 

WOOD,  J.  K.  The  Chemistry  of  Dyeing.  5x7^.  cloth. 
87  pp.  (  Van  Nostrand's  Chemical  Monographs.) 

net,  $0.75 

WORDEN,  E.  C.     The  Nitrocellulose  Industry.    A  com- 


^  ^  LIST  OF  CHEMICAL  BOOKS  17 

pendium  of  the  history,  chemistry,  manufacture,  com- 
mercial application,  and  analysis  of  nitrates,  acetates, 
and  xanthates  of  cellulose  as  applied  to  the  peaceful 
arts.  With  a  chapter  on  gun  cotton,  smokeless  pow- 
der and  explosive  cellulose  nitrates.  Illustrated. 
8vo.  cloth.  Two  volumes.  1239  pp.  net,  $10.00 

-Technology  of  Cellulose  Esters.  A  theoretical  and 
practical  treatise  on  the  origin,  history,  chemistry,  man- 
ufacture, technical  application  and  analysis  of  the  pro- 
ducts of  acylation  and  alkylation  of  normal  and  modi- 
fied cellulose,  including  nitrocellulose,  celluloid,  pyr- 
oxylin, collodion,  celloidin,  gun-cotton,  acetycellulose 
and  viscose,  as  applied  to  technology,  pharmacy, 
microscopy,  medicine,  photography  and  the  warlike 
and  peaceful  arts.  In  ten  volumes.  600  ill.,  12  plates, 
110,000  patent  and  literature  references  to  the  work 
of  12,000  investigators. 

Vol.  VIII.  Carbohydrate  Carboxylates  (Cellulose  Ace- 
tate). Illustrated.  6^x9^.  515  pp.  net,  $5.00 
(Other  volumes  to  follow  at  short  intervals.) 
WEEN,  HENRY.  Organometallic  Compounds  of  Zinc  and 
Magnesium.  5x71/2.  cloth.  108  pp.  (Van  Nos- 
trand's  Chemical  Monographs.)  net,  $0.75 


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